Methods of forming a multilayer tissue implant having a compliance that simulates tissue

ABSTRACT

Disclosed are implantable tissue augmentation devices, methods, and associated tools. The devices include an inflatable body, having an inner layer and an outer layer. A valve is provided for permitting the introduction of and retaining inflation media. At least one pull tab is provided on an end of the implant, to assist in positioning the implant. Kits and systems are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 120 as a continuationof U.S. patent application Ser. No. 11/316,215, filed Dec. 22, 2005 andcurrently pending, which in turn is a continuation-in-part applicationthat claims dual priority from U.S. patent application Ser. No.10/942,728, filed Sep. 15, 2004, issued Jul. 17, 2007 as U.S. Pat. No.7,244,270, and PCT/US2005/033252, filed Sep. 15, 2005, the disclosuresof which are incorporated in their entirety herein by reference.

BACKGROUND OF THE INVENTION

There is a growing demand for cosmetic procedures which augment softtissue to enhance facial appearance. The American Society for AestheticPlastic Surgery reports nearly 8.3 million aesthetic procedures wereperformed in 2003, an increase of 20% from the year before. The mostcommon of these procedures are intended to remove facial wrinkles andlines or augment the lips to restore a more youthful appearance.

Botulinum toxin is used to paralyze the small facial muscles arounddynamic wrinkles in the forehead and around the eyes. Materials thathave been used to smooth non-dynamic wrinkles or augment facial tissues(nasolabial lines, lips, etc.) include injectable soft tissue fillerssuch as silicone, collagen in a variety of forms and formulations suchas Inamed Corporation's CosmoDerm and CosmoPlast, hyaluronic acidderivatives such as Restylene and Hyaloform, and calcium hydroxyapatitemicrospheres such as Radiance. Autologous fat can also be taken from adonor site by liposuction and then injected in the targeted facialtissue. While these injectable fillers are convenient, and some can evenbe done as a simple office procedure, the results are temporary and onceinjected, the filler cannot be removed.

Implanted artificial tissue fillers are well known and are generallyplaced through surgical incisions. These include ePTFE-based tubes,fibers or sheets, including Gore Subcutaneous Augmentation Material(S.A.M.), Advanta, marketed by Atrium Medical, and Ultrasoft andSoftform marketed by Tissue Technologies, now Integra Life Sciences.Surgically implanted tissue fillers can also be derived from biologicsources such as Alloderm from LifeCell Corp. and DuraDerm fromCollagensis, Inc.

Surgically implanted fillers have a number of limitations such asprolonged recovery time due to bruising and swelling which isunacceptable to many patients, risk of infection or granuloma formation,erosion, shrinking and migration. Many patients cannot accept the factthe implant is palpable under the skin because it is firmer than thesurrounding skin. The implanted fillers may also be difficult to remove,should the patient wish to, or a complication arises that demands itsremoval.

The ideal facial tissue filler would be completely biocompatible; easyto place through a relatively small needle, as opposed to through alarge surgical incision; permanent but could be removed either at thetime of the procedure to allow for re-positioning, or at some time inthe future; have a very low risk of infection or immunologic response;would not expand, contact or migrate over time; would not erode; andwould not be noticeable to the patient.

Biocompatible medical devices that have a small enough profile to fitinto a catheter, yet self-expand or are made to expand when such adevice is released from the distal end of the catheter, are ubiquitousin vascular, cardiovascular and neurovascular intervention. Such devicesinclude various types and configurations of self-expanding or balloonexpandable stents, and embolization coils. These devices are oftenconstructed of a metal and can be covered with a polymer such as asleeve of ePTFE.

However, there remains a need for a device of a similar nature that canbe placed within a non-vascular space such as dermal tissue, which canbe enlarged in situ to provide a desired cosmetic or therapeutic result.

SUMMARY OF THE INVENTION

In one embodiment of the present invention, the invention comprises animplantable tissue augmentation device. In one embodiment, the devicecomprises an elongate, flexible tubular body, having a proximal end, adistal end and a cavity, a valved opening on the proximal end, and aclosed distal end. In a preferred embodiment, the device additionallyhas a first configuration and a second configuration, wherein the tissueaugmentation device is transformable from the first configuration to thesecond configuration by introduction of a filler into the cavity via thevalved opening.

In another embodiment of the present invention, the invention comprisesa tissue augmentation device having a first configuration and a secondconfiguration, wherein the first configuration is adapted to fit througha tubular access channel and the second configuration is adapted to filltissue with a tissue augmenting size and shape and wherein the tissueaugmentation device is transformable from the first configuration to thesecond configuration by introduction of a filler into the devicefollowing delivery of the device into the tissue through the tubularchannel.

In a further embodiment of the present invention, the inventioncomprises a kit system, or compilation of items for augmenting tissue,comprising at least one tissue augmentation device having an elongate,flexible body, which is transformable from a first configuration forimplantation to a second configuration for augmentation; a filler tubefor permitting access to the interior of the body; and a filler, fortransforming the body from the first configuration to the secondconfiguration.

In yet another embodiment of the present invention, the inventioncomprises a method of augmenting soft tissue. In one embodiment, themethod comprises identifying a treatment site on a patient; introducinga dissecting tool into the tissue beneath the treatment site; creating atissue plane using the dissection tool; introducing a transformabletissue augmentation device into the tissue plane; and transforming thetissue augmentation device from a first, reduced configuration having afirst volume to a second, enlarged configuration having a second volumewhile at the site. In one embodiment, the second configuration is atleast about 5 times greater than the first configuration.

In one or more of the embodiments described herein, the tissueaugmentation device further comprises at least one port on the proximalend, for accessing the interior of the body.

In one or more of the embodiments described herein, the tissueaugmentation device is transformable from the first configuration to thesecond configuration upon introduction of a filler through the port andinto the device after the device has been delivered into the tissue.

In one or more of the embodiments described herein, the tissueaugmentation device comprises material to encourage fibrous tissueingrowth.

In one or more of the embodiments described herein, the tissueaugmentation device comprises at least one grasping means to allowpositioning of the device at a desired site. In one embodiment, thegrasping means comprises one or more tabs.

In one or more of the embodiments described herein, the tissueaugmentation device comprises an inner layer and an outer layer, whereinthe outer layer comprises a porous material to encourage fibrous tissueingrowth and wherein the inner layer comprises an elastomeric materialthat adds flexibility to the body and is for contact with the fillermaterial.

In one or more of the embodiments described herein, the tissueaugmentation comprises at least two layers, wherein an outer layercomprises ePTFE and an inner layer comprises silicone, polyurethane, ora thermoplastic elastomer. In one embodiment, the device comprises onlyan inner and outer layer. In one embodiment, the device comprises one ormore additional layers. In another embodiment, the device comprises onlya single layer.

In one or more of the embodiments described herein, the tissueaugmentation comprises one or more fluids. The fluid may comprise one ormore liquids. The liquid may comprise saline.

In one or more of the embodiments described herein, the filler comprisesa material that can be manually shaped to a desired configuration beforethe filler transforms to retain a molded configuration.

In one or more of the embodiments described herein, the tissueaugmentation device permits passage of a fill tube, but reseals eithercompletely or substantially following removal of the fill tube. In oneor more of the embodiments described herein, the resealing occurswithout any external intervention (e.g., the device spontaneouslyself-seals).

In one or more of the embodiments described herein, the tissueaugmentation device comprises one or more pierceable septums, whichpermit passage of a fill tube, but which reseal either completely orsubstantially following removal of the fill tube.

In one or more of the embodiments described herein, the tissueaugmentation device comprises a plurality of internal baffles whichdivide an interior cavity of the device into a plurality of chambers orcompartments. The baffles may comprise pierceable septums, which permitpassage of a fill tube, but which reseal either completely orsubstantially following removal of the fill tube.

In one or more of the embodiments described herein, the device comprisestwo or more compartments that are adapted to be filled separately inorder to vary the contour of the filled region.

In one or more of the embodiments described herein, the device isselectively inflated or deflated to achieve a desired contour.

In one or more of the embodiments described herein, the device has adiameter within the range of from about 1 mm to about 8 mm.

In one or more of the embodiments described herein, the device has alength within the range of from about 1 cm to about 6 cm.

In one or more of the embodiments described herein, the device has awall thickness within the range of from about 0.003 inches to about0.020 inches.

In one or more of the embodiments described herein, the tissueaugmentation device has a second configuration that has a diameter ofabout 1 mm to about 10 mm.

In one or more of the embodiments described herein, the firstconfiguration of the device is dimensioned to fit through a tubularaccess channel having a gauge in the range of about 14 gauge to about 20gauge.

In one or more of the embodiments described herein, the firstconfiguration of the device has a diameter of less than about 1.6 mm.

In one or more of the embodiments described herein, the tissueaugmentation device comprises one or more sutures.

In one or more of the embodiments described herein, the tissueaugmentation device is adapted to be substantially uninflated prior toinsertion into the tissue. In other embodiments, the tissue augmentationdevice is adapted to be partially inflated prior to insertion into thetissue.

In one or more of the embodiments described herein, filler is added intothe tissue augmentation device during the implantation procedure and atleast once subsequent to implantation, thereby providing a chronicallyadjustable tissue augmentation device.

In one or more of the embodiments described herein, the tissueaugmentation device is internally segmented to permit the segments to befilled with various volumes of filler material in order to create aspecific profile.

In one embodiment of the present invention, a augmentation system isprovided. In one embodiment, this system comprises the tissueaugmentation device of one or more of the embodiments described herein,and a dissection tool to separate tissue beneath the treatment site andcreate a tissue plane.

In one embodiment of the present invention, a tissue augmentation systemcomprising the tissue augmentation device of one or more of theembodiments described herein, and a tubular access channel is provided.In one embodiment, the tubular access channel comprises a needle,cannula or catheter.

In one embodiment of the present invention, a tissue augmentation systemcomprising the tissue augmentation device of one or more of theembodiments described herein, and a fill tube for providing filler isprovided.

In one or more of the embodiments described herein, the tissueaugmentation device is for use in the treatment of facial scars, lines,or wrinkles.

In one or more of the embodiments described herein, the tissueaugmentation device is adapted to and used for augmenting facial tissue.

In one or more of the embodiments described herein, the tissueaugmentation device is adapted to and used for augmenting facialwrinkles.

In one or more of the embodiments described herein, the tissueaugmentation device is adapted to and used for filling lines, scars, orwrinkles on the body or face.

In one embodiment of the present invention, a plurality of the tissueaugmentation devices is provided. In one embodiment, tissue augmentationdevices are provided in a plurality of various sizes so as to permit theuser to select a desired size. In one embodiment, at least one of thetissue augmentation devices has an inflated diameter of: 0.5 to 2 mm,1.5 to 5 mm, 2 to 6 mm, or 2 to 8 mm.

In one embodiment of the present invention, the invention comprises animplantable tissue augmentation device, comprising at least two flexiblesheets connected to form a plurality of chambers between them, saidchambers being adapted to receive a filler to expand one or more of saidchambers to a desired configuration. In one embodiment, the sheetscomprise a material capable of being pierced by a tube for supplyingfiller to the chambers and self-sealing upon withdrawal of such a tube.In one embodiment, the sheets are bonded together adjacent theirperiphery and between their periphery to form the chambers. In oneembodiment, the sheets are bonded together between the peripheries in agrid-like pattern. In another embodiment, two sheets are provided, eachsheet being formed of multiple layers. In one embodiment, the peripheryis shaped to generally fit the human cheek. In one embodiment, thedevice, in its pre-filled condition, has a thickness of less than about15 mm.

In one or more of the embodiments described herein, the device islocated in a larger sheet arrangement, from which one or more of thedevices may be cut.

In one embodiment of the present invention, the invention comprises amethod of augmenting tissue, comprising implanting a device comprisingat least two flexible sheets connected to form a plurality of chambersbetween them, and selectively filling, partially or fully, one or moreof the chambers therein to achieve a desired contour in the tissue.

There is provided in accordance with one aspect of the presentinvention, a tissue augmentation system. The system comprises a tubularchannel adapted to be placed within human tissue, and a tissue dilatoradapted to pass through the tubular channel. A tissue filling device isprovided, having a first configuration and a second configuration. Thefirst configuration is adapted to fit through the tubular channel andthe second configuration is formed to fill the tissue. The device istransformable from the first configuration to the second configurationupon introduction of a filler into the device after the device has beendelivered into the tissue through the tubular channel.

The tubular channel may be a needle, catheter, cannula, or other accessdevice. The tissue to be augmented may be the skin.

In accordance with another aspect of the present invention, there isprovided a tissue augmentation device. The device comprises an elongateflexible body, having a proximal end and a distal end. At least a firstport is provided on the proximal end, for accessing the interior of thebody. A suture extends from the distal end.

A needle may be provided on the suture, for percutaneous access to atreatment site. The body may comprise a tubular sleeve, which may have acircular or flattened cross section. The body may comprise two sheets ofmaterial bound together along a periphery. The body may also comprisetwo concentric tubular layers. At least a second port may be provided,for accessing the interior of the body. One or more valves may beprovided, for closing the port. In certain embodiments, at least twocompartments may be provided within the flexible body.

In accordance with a further aspect of the present invention, there isprovided a kit for augmenting tissue. The kit comprises at least oneelongate flexible body, which is transformable from a firstconfiguration for implantation to a second configuration foraugmentation. At least one suture is attached to the body. A filler tubeis provided, for permitting access to the interior of the body. The term“filler tube” is used interchangeably with the term “fill tube.” Afiller is additionally provided, for transforming the body from thefirst configuration to the second configuration.

The body may comprise a tubular sleeve, which may have one or aplurality of internal compartments. The body may additionally comprise avalve. At least a second suture may additionally be attached to thebody. The filler may comprise a liquid, and may be polymerizable insitu. The kit may additionally comprise a syringe, for injecting thefiller into the filler tube.

In accordance with a further aspect of the present invention, there isprovided a kit for augmenting tissue. The kit comprises a plurality ofelongate flexible bodies, each of which is transformable from a firstconfiguration for implantation to a second configuration foraugmentation, provided in a plurality of sizes and shapes. At least onesuture is attached to each body. A deployment tube is provided, fordelivering the body to a treatment site. A filler tube is provided forpermitting access to the interior of the body, and a filler is provided,for transforming the body from the first configuration to the secondconfiguration.

In accordance with another aspect of the present invention, there isprovided a kit for augmenting tissue. The kit comprises a plurality ofelongate flexible bodies, each of which is transformable from a firstconfiguration for implantation to a second configuration foraugmentation. The flexible bodies are provided in a plurality of sizesand shapes. At least one suture is attached to each body. A filler tubeis provided for permitting access to the interior of the body, and atleast two different fillers for transforming the body from the firstconfiguration to the second configuration are also provided. The fillersmay have different viscosities, and/or different durometers.

There is provided in accordance with one aspect of the presentinvention, a method of filling tissue. The method comprises the steps ofinserting a tubular channel within the tissue, and inserting a tissuefilling device into the channel. The tubular channel is withdrawn overthe tissue filling device, to leave the tissue filling device within thetissue. The device is transformed to reconfigure the tissue.

The tubular channel may comprise a needle, a cannula, or other accessdevice. The tissue may be the skin.

The transforming the device step may flatten the nasolabial fold. Thetransforming the device step may alternatively enhance the lips.

In accordance with a further aspect of the present invention, there isprovided a method of filling tissue. The method comprises the steps ofinserting a needle into the tissue, and passing a guidewire (e.g.,suture, metal filament, etc.) through the needle. The needle is removed,and a catheter is passed over the wire. A tissue filling device isinserted through the catheter, and the catheter is withdrawn over thetissue filling device thereby leaving the tissue filling device withinthe tissue.

In accordance with a further aspect of the present invention, there isprovided a method of filling tissue. The method comprises the steps ofinserting a needle containing a tissue filling device into the tissue.The tissue filling device is maintained in substantially constantposition relative to the tissue via forward pressure on a systemcomponent in contact with the device such as a filler tube, while theneedle is withdrawn over the tissue filling device, thereby leaving thetissue filling device within the tissue. The tissue filling device isfilled by injecting filler material through the filler tube into thetissue filling device, and the filler tube is removed. The tissue may bethe skin.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thesteps of identifying a treatment site on a patient, and introducing atransformable tissue bulking device beneath the site. The bulking deviceis transformed from a first, reduced volume to a second, enlarged volumewhile at the site.

The introducing step may comprise introducing the device over a wire.The introducing step may comprise introducing the device through a tube.The introducing step may comprise pulling a distal end of the devicewith a distal suture.

The transforming step may comprise introducing a filler into the device.The identifying step may comprise identifying a wrinkle. The site maycomprise a nasolabial fold, an upper lip, a lower lip, a facial fold, orother site where tissue bulking is desired.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thesteps of identifying a treatment site on a patient, and measuring thedimensions of the site. A tissue bulking device having a size and shapeappropriate to the dimensions of the site is chosen from a kit oftransformable tissue bulking devices. The chosen transformable tissuebulking device is introduced beneath the site, and the device istransformed from a first, reduced volume to a second, enlarged volumewhile at the site. The measuring step may comprise passing a suture orother measurement device containing a plurality of markings along thepath to be augmented and counting the number of or reading the markings.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thesteps of identifying a treatment site on a patient, and introducing atransformable tissue bulking device beneath the site. A polymer isinjected into the tissue bulking device, and the tissue bulking deviceis shaped in situ (e.g., by manual manipulation of the surface of theskin, application of a mold, etc.) into a desired configuration. Thepolymer is then caused (e.g., permitted, or actively catalyzed orinitiated by application of an external initiator) to retain the desiredconfiguration.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thestep of identifying a treatment site on a patient, and introducing adissection tool into the tissue beneath the treatment site. A tissueplane is created using the dissection tool, and a transformable tissuebulking device is introduced into the tissue plane. The bulking deviceis transformed from a first, reduced volume to a second, enlarged volumewhile at the site.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thesteps of identifying a treatment site on a patient, and introducing atissue filling device into the tissue beneath the treatment site. Afiller material is injected into the tissue filling device, while thecontour of the treatment site is monitored. Once the treatment site hasachieved a desired contour, injection of filler material isdiscontinued.

In accordance with a further aspect of the present invention, there isprovided a method of augmenting soft tissue. The method comprises thesteps of identifying a treatment site on a patient, and measuring thedimension of the site. A transformable tissue bulking device having asize and shape appropriate to the dimensions of the site is selectedfrom a kit having a plurality of tissue bulking devices. The elasticityof the tissue at the treatment site is assessed, and a filler of aconsistency appropriate to the elasticity of the treatment site isselected from a kit including a plurality of fillers. The selectedtransformable tissue bulking device is introduced beneath the site, andtransformed from a first, reduced volume to a second, enlarged volumewhile at the site.

There is provided in accordance with one aspect of the presentinvention, a method of making an implantable tissue bulking device. Themethod comprises the steps of providing a flexible tubular body, havinga proximal end, a distal end and a central lumen. A closing element ispositioned on the proximal end of the tubular body, and the tubular bodyis everted to position the closing element within the central lumen.

The closing element may comprise one or more elastomeric bands, asuture, a clip, or other biasing element.

The method may additionally comprise the step of tying a suture orpositioning another closing element around the distal end of the tubularbody, to form a closed distal end. The method may additionally comprisethe step of positioning a guidewire through the proximal end and intothe central lumen.

There is provided in accordance with another aspect of the presentinvention, an implantable tissue augmentation device. The devicecomprises an elongate flexible tubular body, having a proximal end, adistal end and a central lumen. A valved opening is provided on theproximal end, and the distal end is closed.

The device may additionally comprise a guidewire extending through thevalved opening. The valve may comprise a closing element surrounding aportion of the tubular body. The tubular body may be everted to positionthe closing element within the central lumen. The closing element maycomprise a suture loop. Alternatively, the closing element may comprisean elastic loop, or a metal loop. The device may additionally comprise adistal suture attached to the distal end of the tubular body.

There is provided in accordance with one aspect of the present inventiona tissue filling device. The device has a first configuration and asecond configuration, wherein the first configuration is adapted to fitthrough a tubular access channel and the second configuration is adaptedto fill tissue with a tissue augmenting size and shape. The device istransformable from a first configuration to the second configuration byintroduction of a filler into the device following delivery of thedevice into the tissue through the tubular channel.

The device may comprise a flexible polymeric tube. The filler maycomprise shape memory wire, a plurality of coils, a liquid, a gel, orbeads suspended in a liquid. The filler may be polymerizable in situ,cross linked in situ, or otherwise change viscosity in situ. The devicemay have proximal and distal ends that are softer than a mid-portion,and may comprise a balloon. The device may be at least partially coveredwith a polymer, such as ePTFE, or a laminate of ePTFE and athermoplastic. The thermoplastic may be polyethylene.

The device may comprise a metallic frame, such as Nitinol frame, havinga polymer coating.

The tubular channel may be a needle, a catheter, a cannula or otheraccess device.

The tissue may be the skin, the gastroesophageal junction, themyocardium or the stomach wall. The tissue may also be in the vicinityof the nasolabial fold, the right or left or both sides of the upper orlower lip, the cheeks, other facial folds, or other site on the bodywhere augmentation is desired.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side elevational cross section through an emptysleeve in accordance with one embodiment of the present invention.

FIG. 2 is a side elevational cross sectional view through a partiallyinflated sleeve.

FIG. 3 is a side elevational cross sectional view through a filledsleeve having a uniform exterior profile.

FIG. 4 is a cross sectional side elevational view through a segmentedsleeve, having customized fill volumes in each segment.

FIG. 5 is a cross sectional view through the distal end of an implant,illustrating a filler tube in position to fill a single segment.

FIG. 6 is a side elevational cross sectional view through a segmentedsleeve having a plurality of internal baffles.

FIG. 7 is a side elevational schematic view of a filler tube inaccordance with one embodiment of the present invention.

FIG. 8 is a side elevational view of an implant removably attached to afiller tube.

FIG. 9 is a side elevational schematic view of the implant of FIG. 8,positioned beneath the skin.

FIG. 10 is a side elevational view of an implant removably attached to afiller tube.

FIG. 11 is a side elevational schematic view of the implant of FIG. 10,positioned beneath the skin.

FIG. 12 is a side elevational schematic view of an implant and fillertube assembly, positioned within a delivery cannula.

FIG. 13A through 13D illustrate an assembly sequence for a soft tissuebulking device in accordance with one embodiment of the presentinvention.

FIG. 14 illustrates a bulking device as in FIG. 13D, additionallyshowing a guidewire.

FIG. 15 depicts non-limiting examples of potential locations forimplants on the face.

FIG. 16 is an overhead plan view of a segmented malar mid-face implantin its deflated state, according to one embodiment of the invention.

FIG. 17 is a representation of a segment malar mid-face implant in itsinflated state according to one embodiment of the invention.

FIGS. 18A-F are cross-sections of various preferred tube-based andsheet-based implants in various configurations. FIG. 18A illustrates theconfiguration of a tube-based, taut-filled implant. FIG. 18B shows atube-based, slightly flaccid implant. FIG. 18C shows a tube-basedmarkedly flaccid-filled implant. FIG. 18D shows a sheet-based,taut-filled implant. FIG. 18E discloses a sheet-based, flaccid filledimplant. FIG. 18F shows an example of a sheet-based implant with twosheets of differing compliances, that may be desirable in order to makean asymmetric cross-section upon inflation.

FIG. 19 illustrates various wrinkle lines of the face that may betreated with the disclosed implants, according to one embodiment of theinvention.

FIG. 20 is an inflatable nasolabial implant in a deflated state,according to one embodiment of the invention.

FIG. 21A is a valve assembly, according to one embodiment of theinvention.

FIG. 21B is an exaggerated cross-sectional view of the valve assembly ofFIG. 21A.

FIG. 21C is a valve with a nitinol coil plug, according to oneembodiment of the invention.

FIG. 21D is another valve with a nitinol coil plug in a differentconfiguration, according to one embodiment of the invention.

FIG. 21E is a valve with a “paper clip” configuration of the nitinolcoil plug, according to one embodiment of the invention.

FIG. 21F is another variation of a nitinol coil plug, according to oneembodiment of the invention.

FIG. 21G is a valve with a folded O-ring configuration, according to oneembodiment of the invention.

FIG. 22 is an inflatable nasolabial implant inflated to its maximallyrecommended fill volume, according to one embodiment of the invention.

FIG. 23A illustrates a cross-sectional view of a nasolabial implantfully inflated as recommended, near its distal end, according to oneembodiment of the invention.

FIG. 23B illustrates an embodiment of an implant with variations inlamination, in which the porous outer material is affixed to theunderlying elastomeric material in wound or interrupted configurations,for example, helical, bands, stripes, and the like.

FIG. 23C illustrates a cross-sectional view of a nasolabial implantinflated to less than the maximally recommended fill volume, near itsdistal end, according to one embodiment of the invention.

FIG. 23D is a view of a valve assembly within an embodiment of aninflated nasolabial implant, and illustrates the dual layer, bonded, andunbonded areas.

FIG. 24A is a cross-sectional view of a nasolabial implant fullyinflated as recommended, near its proximal end according to oneembodiment of the invention.

FIG. 24B is a cross-sectional view of a nasolabial implant inflated toless than the maximally recommended fill volume, near its proximal endaccording to one embodiment of the invention.

FIG. 25 shows a general shape of an advantageous nasolabial implant inwhich the distal end is to the left and the proximal end to the rightaccording to one embodiment of the invention.

FIG. 26A illustrates a step in creating an implant laminationsubassembly where silicone tubing is slipped over an ePTFE mandrel,according to one embodiment of the invention.

FIG. 26B illustrates a step in creating an implant laminationsubassembly where ePTFE tubing is slid over the small diameter end of amandrel until aligned with the silicone tube end, according to oneembodiment of the invention.

FIG. 26C illustrates a step in creating an implant laminationsubassembly where a shrink tube is placed over the end of the ePTFEtubing, according to one embodiment of the invention.

FIG. 26D illustrates a step in creating an implant laminationsubassembly where heat is applied until the tube is shrunk down using anhot box, according to one embodiment of the invention.

FIG. 26E illustrates a step in creating an implant laminationsubassembly after application of heat to the shrink tube, andapplication of an O-ring.

FIG. 26F is a schematic diagram showing application of silicone adhesiverelative to various other components of a lamination subassembly,according to one embodiment of the invention.

FIG. 26G illustrates a step in creating an implant laminationsubassembly by application of adhesive to the silicone tube, accordingto one embodiment of the invention.

FIG. 26H illustrates a step in creating an implant laminationsubassembly where ePTFE is everted over the silicone tube usingtweezers, according to one embodiment of the invention.

FIG. 26I illustrates a step in creating an implant laminationsubassembly immediately prior to the application of tape to evert theePTFE over the silicone tube, according to one embodiment of theinvention.

FIG. 26J illustrates a step in creating an implant laminationsubassembly where tape is applied to evert the ePTFE over the siliconetube, according to one embodiment of the invention.

FIG. 27A illustrates various components required to create an implantvalve subassembly, according to one embodiment of the invention.

FIG. 27B shows a step in creating an implant valve subassembly, where avalve tube is slid onto a small needle, according to one embodiment ofthe invention.

FIG. 27C shows a step in creating an implant valve subassembly, wherethe tip of the small needle is then inserted into the tip of a 20-gaugeprecision dispense tip, according to one embodiment of the invention.

FIG. 27D shows a step in creating an implant valve subassembly, where ahalf-hitch knot is tied around the end of a valve plug, according to oneembodiment of the invention.

FIG. 27E shows a step in creating an implant valve subassembly, wherethe valve tube is slid onto the valve plug, according to one embodimentof the invention.

FIG. 27F shows a step in creating an implant valve subassembly, where amandrel is inserted into the valve tube, according to one embodiment ofthe invention.

FIG. 27G shows a step in creating an implant valve subassembly, wherethe trimmed valve plug protruding from the valve tube, according to oneembodiment of the invention.

FIG. 27H shows a step in creating an implant valve subassembly, where ahalf-hitch knot is tied around the free end of the neck tube.

FIG. 27I shows a step in creating an implant valve subassembly, where asuture is threaded onto a precision dispense tip, and the neck tube isdrawn into the shaft until the precision dispense tip and the mandrelabut each other.

FIG. 27J illustrates a completed valve subassembly, according to oneembodiment of the invention.

FIG. 28A illustrates various components utilized to seal the proximalend of the lamination subassembly, according to one embodiment of theinvention.

FIG. 28B illustrates a step in sealing the proximal end of thelamination subassembly, where a proximal shim is inserted into thelamination subassembly.

FIG. 28C illustrates a step in sealing the proximal end of thelamination subassembly, where the neck of the proximal shim is alignedto be parallel to the axis of the lamination subassembly.

FIG. 28D illustrates a step in sealing the proximal end of thelamination subassembly where a hard jaw clamp is placed across thelamination subassembly.

FIG. 28E illustrates a step in sealing the proximal end of thelamination subassembly where the end of the lamination subassembly isfilled with adhesive.

FIG. 28F illustrates a step in sealing the proximal end of thelamination subassembly where the adhesive in the lamination subassemblyis smoothed out with fingers.

FIG. 28G illustrates a step in sealing the proximal end of thelamination subassembly where the lamination subassembly is placed on aproximal seal fixture.

FIG. 28H illustrates a step in sealing the proximal end of thelamination subassembly where the proximal shim is removed from thelamination subassembly.

FIG. 28I illustrates a step in inserting the valve subassembly into thelamination subassembly where a hypo tube is inserted into the laminationsubassembly.

FIG. 28J illustrates a mandrel with valve subassembly in the laminationsubassembly.

FIG. 28K illustrates the valve subassembly after withdrawal of the hypotube, leaving the mandrel and neck tube contained in the neck of theproximal seal.

FIG. 28L illustrates a step in inserting the valve subassembly into thelamination subassembly where the mandrel is slid toward the distal endof the device without moving the neck tube or the valve subassembly.

FIG. 28M illustrates a step in inserting the valve subassembly into thelamination subassembly where adhesive is placed into the proximal end ofthe device after placement of a hard jaw clamp.

FIG. 28N illustrates a step in inserting the valve subassembly into thelamination subassembly where a razor blade is used to trim the proximaltab along the proximal seal line.

FIG. 28O illustrates a step in inserting the valve subassembly into thelamination subassembly where a portion of the proximal tab is cut offusing a razor.

FIG. 29A illustrates various components utilizable to seal the distalend of the implant, according to one embodiment of the invention.

FIG. 29B illustrates the lamination subassembly being inserted into thedistal seal fixture.

FIG. 29C illustrates the clamping plate being lowered and screwed intoplace, aided by an arbor press, after the lamination subassemblies areproperly aligned.

FIG. 29D illustrates the open end of a lamination subassembly beingfilled with adhesive.

FIG. 29E illustrates a seal plate being lowered over the devices andscrewed into place.

FIG. 30, line A illustrates a horizontal plane superior to thevermillion border of the lips.

FIG. 31 is a cross-sectional view, generally through line A in FIG. 30,illustrating the anatomy of the various subdermal layers.

FIG. 32 is an embodiment of a specialized grasper, with the distal tiparea of interest identified, according to one embodiment of theinvention.

FIG. 33 is a detailed view of the tip of the specialized grasper of FIG.27 according to one embodiment of the invention.

FIG. 34 is another line drawing of the specialized grasper, andillustrates the handle portion according to one embodiment of theinvention.

FIG. 35 is a three-dimensional view of the specialized grasper accordingto one embodiment of the invention.

FIG. 36 is an alternative embodiment of a specialized grasper with anaxially symmetric slot and alternative handle configuration.

FIG. 37 is a cut-away view of the specialized grasper of FIG. 35.

FIG. 38 is a three-dimensional view of the specialized grasper of FIG.36 according to one embodiment of the invention.

FIG. 39 is a detail view of the tip of the specialized grasper of FIG.36 illustrating the axially symmetric slot.

FIG. 40 is an example of an alternative embodiment for the handle of aspecialized grasper, with the handle in an off-axis position.

FIG. 41 is another example of an alternative embodiment for the handleof a specialized grasper, with the handle in an off-axis position.

FIG. 42 is another example of an alternative embodiment for the handleof a specialized grasper.

FIG. 43 is another example of an alternative embodiment for the handleof a specialized grasper, utilizing a ratcheting mechanism.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The invention is, generally, a system and method for volume augmentationof tissue in a living being, preferably, a human. The system generallycomprises a tissue-filling device and a method for delivering thetissue-filling device into tissue. The tissue-filling device comprisestissue filler material and an enclosing sheath. Preferably, theenclosing sheath forms a container that is filled.

The volume augmentation methods and devices described in embodiments ofthe present patent are intended to be used for tissue bulking in avariety of circumstances, depending on the need. For example: ingastroenterology, wherein increasing the volume of tissue at thegastro-esophageal junction can be used to treat gastro-esophageal refluxdisease, and increasing the thickness of the gastric mucosa to decreasethe volume of the stomach to treat morbid obesity; in urology, whereplacing filler radially around the urethra at the neck of the urinarybladder can ameliorate incontinence; and in cardiology, whereby tissuefiller may be placed in the ventricular wall to decrease the volume ofthe left ventricular chamber to treat heart failure, or in thepericardial space to place pressure on the outside of the heart, alsointended to decrease the volume of the heart chambers and thereby treatheart failure; and in other applications well known to those skilled inthe art. In any of these clinical applications, the tissue-fillingdevice may be combined with any number of other bioactive substanceswhich may be released from the filler itself over time, or be injectedconcurrently.

One preferred use of the present invention is in the field of cosmeticplastic surgery wherein the system is used for augmentation in thedermis or subdermis to treat skin contour deficiencies caused by variousconditions, including aging, environmental exposure, weight loss, childbearing, surgery, disease such as acne and cancer, or combinationsthereof, or for beauty enhancement. The tissue augmentation method ofpreferred embodiments of the present invention is particularly suitablefor treating frown lines, worry lines, wrinkles, crow's feet, facialscars, or marionette lines, or to augment facial features such as thelips, cheeks, chin, nose or under the eyes. Treatment of a patient mayconsist solely of using a tissue-filing device, or the tissue-fillingdevice may be used as part of additional cosmetic surgery such as a faceor brow lift. The characteristic of change from first configuration tosecond configuration makes the tissue-filling device desirable for usein endoscopic surgery. The tissue augmentation device may also be usedfor breast augmentation, and regions of the body that need volumeenlargement during reconstructive plastic surgery, such as after traumaor tumor resection.

The sleeve can be embodied as a variety of structures, and constructedof a variety of materials. The term “sleeve” as used herein is meant toinclude any structure adapted to substantially separate a fillermaterial from the tissue in which the tissue-filling device isimplanted. The term “skin” and “membrane” is used interchangeably andhas the same scope of meaning as sleeve.

In one embodiment, a sleeve is placed in the tissue to be filled, and asa second step, the sleeve is filled with material such that the sleeve,when filled, creates a volume adequate to alter the tissue contour asrequired to produce the clinical result. Filling can either beaccomplished through the device used to implant the sleeve, or through aseparate device, or both, as will be discussed. In an alternativeembodiment, the tissue-filling device is constructed prior to itsimplantation in the tissue by filling a sleeve with a tissue filler andthe assembled tissue-filling device is placed in the tissue. In stillanother alternative embodiment, the tissue filler may be of more thanone component such that one (or more) component of the tissue filler isin place inside the sleeve before the sleeve is placed in the tissue tobe augmented, and a second component (or components) are placed withinthe sleeve after the sleeve has been placed in the tissue, thecombination of the components than constituting the final fillermaterial.

The sleeve can be compliant or non-compliant, or a combination ofcompliant and non-compliant components. The sleeve may be made of abiocompatible but non-biodegradable material. Suitable materials includeePTFE, PTFE, polypropylene, polyacrylamide, polyurethane, silicone,polymethylmethacrolate, Dacron, metals, tubes or meshes of nickeltitanium alloys such as Nitinol, silver, gold, platinum, or stainlesssteel. The sleeve can comprise a plurality of layers of materials. Otherbiocompatible materials are well known in the art, as, for example,disclosed in U.S. Pat. No. 5,630,844 to Dogan.

If fibrous tissue ingrowth is desired, then the sleeve can be made of orcovered with ePTFE with a pore size of in the range of from about 40 toabout 100μ. If the filler material is, or becomes, non-flowable, thesleeve may be made of a biocompatible and biodegradable material chosenfrom any of various polylactides, polyglycolides, polycaprolactones,polyanhydrides, polyamides, polyurethanes, polyestera-mides,polyorthoesters, polydioxanones, polyacetals, polyketals,polycarbonates, polyortho-carbonates, polyphosphazenes,polyhydroxybutyrates, polyhydroxyvalerates, polyalkylene oxalates,polyalkylene succinates, poly(malic acid), poly(amino acids),poly(methyl vinyl ether), poly(maleic anhydride), chitin, chitosan, andcopolymers, terpolymers, or higher poly-monomer polymers thereof orcombinations or mixtures thereof, such that the initial implantation ofthe filler device comprises a sleeve and filler material, but over time,the sleeve is resorbed and only the filler material is left behind toaugment the tissue.

In one embodiment, the sleeve comprises an outer layer of ePTFE of about40 to 100μ pore size and about 0.001 to 0.010 inches in thickness toencourage fibrous tissue ingrowth, and an inner sleeve of polyethyleneor similar material of about 0.001 to 0.010 inches in thickness to addflexibility to the sleeve and to more completely contain the fillermaterial. Such double layer structure is particularly suited where theePTFE is permeable or semipermeable to the filler material, such as whenthe filler material is, or contains a component of, water.

The sleeve may contain, or be contained by, a skeletal structure such asstruts of a metal including alloys such as nitinol, stainless steel,gold, or platinum, a polymer such as PLA or PLG, or any material ofsufficient durometer or structural integrity to provide support of thesleeve or to provide for a three-dimensional shape. Struts can extend inan axial direction, a circumferential direction or both depending uponthe desired clinical performance. Additionally, the struts may haveanchor elements or hooks which extend through the sleeve, adapted tostabilize the tissue-filling device within the tissue.

In one embodiment, the sleeve itself is highly flexible. Therefore, thematerial should be thin, such as within the range of from about 0.001inches to about 0.010 inches. The sleeve may be manufactured to be offixed length and shape, with a plurality of lengths and shapes providedin a kit, depending on the need to fill a specific region of tissue in aparticular patient, or the sleeve may be cut to size at the clinicalsite as a part of the implantation procedure. For a given region to befilled, more than one tissue filling device may be placed to achieve agiven desired contour. In one embodiment, a plurality of sleeves areprovided that are bound together to create a bundle.

The tissue-filling device may be provided in a kit which includes one ormore sleeves, and one or more filler materials. Or the sleeve may besupplied separately in a kit, and another kit includes one or morefiller materials. Or the kit may consist solely of one or more sleeves,and the surgeon provides the filler material from an alternate source.

The sleeve may have a constant inflated diameter, generally 1-10 mm, orit may have an inflated diameter that varies along its length dependingon the desired contour of the augmented tissue. For glabellar folds, theinflated diameter is, preferably, 0.5 to 2 mm. For lips, the inflateddiameter is, preferably, 1.5 to 5 mm. For the upper lip, the inflateddiameter preferably varies along its length adapted to form the “m”shape of the upper lip. For the lower lip, the sleeve generally tapersat the proximal and distal end, with a larger diameter of 2 to 8 mm atthe central portion. In addition, for the lower lip, the profile of thesleeve will be generally a flattened “u” shape adapted to follow theprofile of the lower lip. For nasolabial folds, the inflated diameteris, preferably, 2 to 6 mm, with tapering at the proximal and distalends. In one embodiment, the sleeve comprises a series of segments suchthat the internal diameter of each segment is greater than the internaldiameter of that portion of the lumen between segments. Further, thesleeve may have internal segmentation embodied by a series of valves orbaffles. In the case of a segmented sleeve, each segment may be filledwith a different volume of filler material in order to create a profilecustomized along the axial length of the implant to suit the specificclinical need. The sleeve may have supporting struts, such as a skeletonmade from filaments, where said filaments may be composed of anybiocompatible material adapted to provide structure.

A valve, or a plurality of valves, can be affixed to one or both ends ofthe sleeve, or along any portion of the wall of the sleeve, in order toprevent filler material from escaping into the surrounding tissue. Therequired integrity of the valve is dependent on the type and viscosityof the filler material. For example, if the filler material gels inplace, or the filler is composed of beads of sufficient size, then thevalve may not need to close tightly. In one embodiment, the valve is oneor more elastomeric bands that encircles the proximal end of the sheath.In another, the valve is one or more elastomeric bands placed, duringconstruction of the tissue filling device, 1 to 4 mm, distal from theproximal end of the sheath, and then when the sheath is turned insideout during its construction, the valve is placed on the interior portionof the sleeve, enhancing the ability of the valve to remain closed asthe sleeve is filled with filler material. In another, the valve is aband of nitinol adapted to form a spring closure at the proximal end ofthe sheath. Other valves known in the art include, for example, U.S.Pat. No. 5,779,672 to Dormandy or U.S. Pat. No. 6,102,891 to van Erp. Inaddition to valve placement at the proximal end of the sheath, valvesmay be deployed at a plurality of locations within the sheath to formsegments, which then allows individual segments to be filled withdifferent amounts of filler material.

The filler material can be any of a number of biocompatible substancesand may be of various physical states or combinations thereof, such as anon-viscous liquid, a viscous liquid, a gel, a powder, beads, flakes,continuous or discontinuous fibers, coils, fiber balls or mixturesthereof. The filler material may be transformable from a first state topermit introduction into the sheath, to a second state once inside thesheath. Combinations, such as a fiber carried within a liquid or gel arewell within the contemplated scope. For example, the filler can comprisea substantially linear filament which itself can be made of a variety ofmaterials such as nitinol, various biocompatible polymers well known tothose skilled in the art, ePTFE, Proline or any biocompatible materialwith adequate strength to alter the contour of the tissue in which it isinjected. The filler material may comprises any of a number of materialscommercially available and sold as tissue fillers, such as Zyplast™,available from Inamed Aesthetics; Restylane™, available from Q-Med andGenzyme, Inc.; Hylaform™, available from Inamed Aesthetics; Artecoll™available from Artes, Inc.; Radiance™ available from Bioform, Inc.; orSculptura™ PLA filler available from Aventis, Inc.

Other embodiments of the filler material include a flexible random orregular coil; knit fibers; woven fabric; a series of filaments woundaround each other, a compressible or non-compressible sponge material, aclosed or open cell foam, or any others depending on the specific needas is well known to those skilled in the art. The filler material couldbe a set of objects connected with a outer membrane or an axialfilament, or could be a series of discrete objects. If it is desiredthat the tissue-filling device be visible by x-ray or fluoroscopicimaging, then radio-opaque coatings such as triazoate, barium salts ortantalum can be included in the filler material. If ultrasonicvisualization is required, small trapped air bubbles or otherechocontrast material can be included in the filler material. The fillermaterial may contain a colored dye in order to render the tissue fillingdevice less visible from outside the tissue.

One class of fillers comprises a mix of solid particles and a carrier.One solid particle comprises micronized particles of ePTFE. Othermaterials that are suitable for use in the present invention include,but are not limited to, PDS II (polydioxanone, a monofilament), Nurolon(a long chain aliphatic polymer Nylon 6 or Nylon 6, 6) Ethilon (a longchain aliphatic polymer Nylon 6 and Nylon 6, 6), Prolene (Polypropylene,isotactic crystalline stereoisomer of polypropylene, a synthetic linearpolyolefin), Vicryl (copolymer made from 90% glycolide and 10%L-lactide), silk, Monocryl (poly-E-caprolactone), polylactide,polyglycolide, poly lactide-co-glycolide, Medpor (biocompatible(micronized) polyethylene), BIOGLASS (bioactive glass particulate), orpolyhydroxyvalerate.

Carriers that may be suitable for use in the present invention eitheralone, as a filler, or in combination with particles include, but arenot limited to, polyvinylpyrrolidone (PVP), silicone oil, vegetable oil,saline, gelatin, collagen, autologous fat, hyaluronic acid, autologousplasma, CO₂ or other gas, and other physiological carriers.

Another class of fillers includes liquids, gas or gels without discretesolid particles. For example, PVP may be used alone or in combinationwith other agents. PVP is a water-soluble polyamide that possessesunusual complexing and colloidal properties and is physiologicallyinert. PVP is commercially available as a biocompatible gel that isfreely transported through the body and is excreted unchanged by thekidneys. This gel has trade names such as Au24k and Plasdone C-15 andPlasdone C-30, and comprises macromolecules from the plasdone family,having the empirical formula (CHCH₂)₂N(CH₂)₃—CO. Polymers of this familyhave been used as binders, extenders, and vehicles for a variety ofmedications for nearly fifty years, and would be expected to be welltolerated and quickly removed from the body in the event of a valvefailure, if the sleeve were to rupture or leak, or if material weremistakenly injected into the tissue, rather than into the sleeve, duringthe implantation procedure.

PVP is available commercially in many molecular weight ranges and ispolymerized to have an average molecular weight in a particularsolution. For example, PVP is available in solutions of an averagemolecular weight of 10,000 daltons, 40,000 daltons and 360,000 daltons.Preferably, the PVP is less than about 60,000 daltons to allow foreasier renal excretion. PVP is also defined by its viscositymeasurement, or K value. K values range from approximately less than 12to 100. PVP compositions which may be desirable with the presentinvention are within a range of K values of from about 12 to 50. PVP iscommercially available from International Specialty Products, Inc., GAFChemical Corp., Wayne, N.J., USA, and from BASF Aktiengesellschaft,Germany. In use, the gel polymer may be diluted with deionized water orsaline to produce the desired viscosity, is sterilized, and placed incartridges for injection. Alternatively, the dehydrated polymerparticles may be placed within the sleeve prior to its being placed inthe tissue to be augmented, and sterile saline added after the sleevehas been placed, resulting in gel formation within the sleeve, andthence expansion of the tissue. Alternatively, the dehydrated polymerparticles may be supplied in a sterile container and reconstituted withsaline or water just prior to filling the sleeve.

Once the filler material is inside the sleeve, its material state orchemical structure may be altered via a number of mechanisms, such asthe addition of a second material acting as a catalyst, heat or cold,change in pH, ultrasound or light, or the state change may happenspontaneously over a period of time. If the material changes its stateover time, that time would ideally be in the range of 10 to 30 minutesfrom injection so that the clinician can mold the shape by manualpalpation to a desired configuration before the filler transforms toretain its molded configuration. Alternatively, the state change wouldtake place over 24 to 48 hours so the patient can sculpt his or her ownfiller configuration. In one embodiment, the filler material is abiocompatible polymer which fills the sleeve in a relatively flowablestate, is molded from the skin surface by the operator to the desiredshape, then light of the appropriate wave length (e.g., UV) is directedat the skin in order to convert the liquid to a non-flowable gel, whichgel retains the desired suppleness. In one embodiment, the gel comprisesa backbone of PEG and/or PVA, with PLA and/or PLG side groups attachedto allow for biodegradability of any gel which fails to fill the sleeveor leaks out, and methylacrylates subunits attached to the backbone toinduce photopolymerization with light of wavelength about 400-500 nm.

The filler material may be capable of reversing its state change, viaany of the mechanisms describe above, to allow for subsequent removal ofthe filler material by aspiration via a channel placed in the sleevefrom outside the tissue. In one embodiment, the channel is a needlewhich contains or is surrounded by an ultrasound crystal such that whenthe needle is inserted into the sleeve and energy is supplied to theultrasound crystal, causing it to vibrate in the range of 100 khz to 1megahertz, the gelled filler material is broken down into a flowablematerial allowing for aspiration through the needle.

In another embodiment, the filler material comprises a purified proteinsuch as available from Gel-Del Technologies and described in U.S. Pat.No. 6,342,250 and U.S. Patent Application Nos. 20030007991, 20020106410,and 20020028243, which turns into a gel at body temperature and can bechanged back into a flowable liquid by application of cold.

In another implementation of the invention, the tissue filling devicecomprises a sheath and a volume of internal foam. In this embodiment, avalve may not be required, since the foam structure itself acts toprevent filler from escaping from the sleeve. The foam may be astructure having an open or closed cell configuration. In oneembodiment, the foam is a closed cell elastomer that is highlycompliant, and the sheath is one of the materials noted above. The foammay be biocompatible polyurethane. The sheath may be ePTFE which isbonded to the outside of the foam. In use, the tissue filling device isplaced in the tissue either directly or via the pull through sewingmethod previously described. Once in place, the tissue filling device isinjected from a site or sites externally to the tissue to be filled,such as from the surface of the skin, with a fluid, such as water,saline, silicone, a hydrogel, or any of the filler materials describedabove including combinations of solid or gel particles or filamentswithin the fluid carrier. Preferably, a small hollow structure is usedto inject the filler material, such as a 25-32 gauge hypo-tube orneedle. This results in local enlargement of the tissue filling deviceas the closed cell foam is filled in the region in which the filler isinjected. Additional sites along the tissue filling device are injectedin order to customize the shape of the augmentation. If too much fillerhas been injected in a region, filler can be removed by re-entering theregion that needs to be shrunk, and then withdrawing filler. The entryof the hypo-tube or needle into the region that needs to be shrunk canbe via the same route through which the region was filled, or anotherpathway may be taken, such as through the skin generally perpendicularlyto the axis of filling. Thus, in one embodiment, a device according toany of the embodiments described herein is selectively inflated ordeflated to achieve a desired shape or contour. Alternatively,additional filler material can be added during the procedure, or at anylater time as desired.

Thus, in one embodiment, filler material is added into a device(according to any of the embodiments described herein) during theimplantation procedure and, optionally at least once subsequent toimplantation. In another embodiment, the device is adapted to be atleast partially inflated two or more times after insertion into thetissue, thereby providing a chronically adjustable device. In oneembodiment, the device is implanted and inflated (e.g., filled) in oneprocedure or on the same day, and adapted to be further inflated (e.g.,filled) on another day. These embodiments are particularly advantageousbecause they offer the recipient the ability to fine tune the contourand appearance of the augmentation.

The foam body is thus constructed of a cellular foam matrix having amultiplicity of cells which divide the interior volume of the implantinto compartments numbering from 100 to 1,000,000 depending on thefiller material chosen and the desired feel of the filled tissue. Thecellular foam material may be a thermoset or thermoplastic polymer.Preferably, the cellular foam material has elastomeric qualities but maybe of a non-elastomeric polymer foam. The shape of the foam bodyinfluences the basic range of shapes of the implant and for many wrinkleapplications will be an elongate body having in an uninflatedconfiguration a length of at least about 5 times and often at leastabout 20 times its average un-inflated cross section. The particularmaterial or materials chosen for constructing the foam body will depend,at least in part, on the density or hardness of the tissue to besimulated.

In certain implementations, the foam body may have an “open-cell”structure, the cells being interconnected with one another by passagesthat permit intercellular communication of the fluid filler. Thepassages interconnecting the cells 20 allow the flow of fluid fillerfrom cell to cell, which may create a hydraulic cushioning effect uponlocalized deformation of the implant by external pressure. The hydrauliccushioning effect created by intercellular fluid communication may helpto impart realistic shape and tissue-like consistency to the implant.The viscosity of the filler at body temperature is preferably related tothe passage size to inhibit excessive free flow between cells in theabsence of external pressure.

The foam body may have a uniform cellular density throughout, or mayhave a cellular density that varies throughout one or more regions,i.e., a cellular density gradient. In the case of an embodiment thatincludes one or more regions 30, 32 having a cellular density gradient,the regions 30, 32 will have different average cellular densities. Theaverage cellular density of a region can be selected to cooperate withthe viscosity of the filler to influence the response of the implant toexternal pressure.

In another embodiment, the open cell structure may be placed within acourser closed cell structure, such that the open cell foam iscompartmentalized into regions such that filler remains in a givenregion, and each region may be filled separately in order to vary thecontour of the filled region. In one embodiment, the device according toany of the embodiments described herein, is compartmentalized andadapted to be filled separately in order to vary the contour of thefilled region. In some embodiments, certain compartments are leftunfilled or partially filled, and may be filled at a later date toachieve or alter a particular shape or contour.

The sleeve for the foam filled embodiment may comprise any of thematerials identified previously, as well as linear aliphatic polyetherurethane; linear aliphatic polyester urethane; cyclic aliphaticpolyether urethane; cyclic aliphatic polyester urethane; aromaticpolyether urethane; aromatic polyester urethane; polybutylene;polypropylene; crosslinked olefinic elastomers;styrene-ethylene/butylene-styrene block copolymer; or any otherbiocompatible material which is substantially radiolucent under standardmammographic or other imaging protocols and intensities. The fluidfiller may comprise a biocompatible triglyceride, serum, salinesolution, or another biocompatible material which is substantiallyradiolucent under standard mammographic protocols and intensities.

The foam body may also be made of a material which is substantiallyradiolucent under standard mammographic or other imaging protocols andintensities. The foam body may be constructed ofstyrene-ethylene-butylene-styrene copolymer; polyethylene; polyurethane;and polytetrafluoro-ethylene; or another biocompatible material which issubstantially radiolucent under standard mammographic or other imagingprotocols and intensities.

Coatings can be applied to all or a portion of any of the sleevesdisclosed herein, either on the outside or the inside thereof. Methodsof applying coatings to biocompatible substances are well known in theart. See, for example, U.S. Pat. Nos. 6,660,301 to Vogel, 6,368,658, and6,042,875. The formation of and coating with hydrogels is disclosed inU.S. Pat. No. 6,652,883 to Goupil. Coatings that make the sheath stickysuch as fibronectin or vitronectin or laminin can be used if desired toinhibit movement of the sheath relative to the tissue. If it is desiredthat the sheath be visible by x-ray or fluoroscopic imaging, thenradio-opaque coatings such as triazoate, barium salts or tantalum can beused on the sheath.

Coatings can also be applied with a biologically active or therapeuticeffect, as needed in the clinical application. For example, growthfactors such as fibroblast growth factor, anti-inflammatory agents suchas corticosteroids to reduce the amount of fibrosis, antibiotics toreduce the risk of infection on the implant, and anesthetics such aslidocaine, procaine or marcaine to decrease pain. In order to modulatefibroblast proliferation, TNP-470, a potent angiogenic inhibitor, canserve as a coating or a co-injectate. Alternatively, it may be desirablefor the sheath to be coated with a tissue adhesive, such as Dermabond™,available from Ethicon/Johnson and Johnson, Inc.; or Focalseal™,available from Focal, Inc. to decrease the motion of the tissue implantdevice relative to the tissue. This is important since relative motioncan prevent proper healing and anchoring of the device to the tissuewhich could eventuate in erosion. In one embodiment, the sheath isconstructed of expanded polytetrafluoroethylene coated with fibrin gluecontaining fibroblast growth factor 1 (FGF1) and heparin.

Generally, the means for filling the sheath is provided by one or moresubstantially tubular structures adapted to be placed within the sheathduring filling, and removable after the sheath has been filled to thedesired volume. In one embodiment, the filler tube can be replaced inthe sheath after its removal. The filler tube can comprise a variety oftubular structures, depending on the need, including a needle, acompliant or non-compliant plastic tube, or a metal hypotube comprisedof stainless steel, nitinol, or any of a variety of materials asappropriate in view of the structure of the implant and desired fillingprotocol. The tube may have a variety of cross sectional profilesincluding round, oval, and flattened, depending on the clinical need andthe shape of the sleeve to be filled.

In one embodiment, the tissue filling device is constructed and used asfollows. The sheath has a proximal end and a distal end. A guide rail,which has a distal end and a proximal end, is adapted so that its distalend extends beyond the distal end of the sheath, then extends throughand within the sheath from distal end to proximal end, and then emergesfrom the proximal end of the sheath such that the proximal end of theguide rail is proximal to the proximal end of the sheath. The guide railis of small diameter, preferably 0.1-1.0 mm, and can comprise anyappropriate filamentous material such as absorbable or non-absorbablesuture, a metal such as stainless steel or nitinol, or any material orcombination of materials adapted to allow a filler tube to slide overthe guide rail and into the interior of the sheath. The guide rail maybe coated with a material such as a hydrogel, silicone, ePTFE or PTFE toincrease its lubricity.

A sew-through method of implanting the tissue filling device is asfollows. A sewing needle is attached to the distal end of the guide railusing any of a number of methods as are well known in the art. Thesewing needle can be straight or curved, and of small diameter,preferably 0.1-1.0 mm. Where the guide rail engages the distal end ofthe sleeve, the sleeve is substantially bonded to the guide rail suchthat filler material cannot escape from the distal end of the sleeve.The guide rail then remains unattached to the sleeve. The filler tubeand attached syringe is adapted to ride over the guide rail in order forthe filler tube to be placed in the sleeve, and removed therefrom afterthe sleeve has been filled.

In use, the surgeon measures the length of the path he wishes to filland picks the sleeve assembly of the appropriate length from a kit ofsuch sleeves. The sewing needle is placed by the surgeon into the skinalong the path that he wishes to augment, stopping before the distal endof the sleeve emerges from the skin, and taking care that the proximalend of the sleeve is within the tissue. If it is not, the sleeve may bepulled all the way through the tissue from the distal end, thus removingit completely from the tissue. In this case, the surgeon may chose asleeve of a different length, or may chose to enter the tissue with thesewing needle at a more proximal location, so that the entire sleeveultimately lies within the tissue. The surgeon may put manual tractionon the tissue in order to guide the needle along the desired path. Thefiller tube is advanced along the guide rail into the interior of thesleeve until the distal end of the filler tube is located at or near thedistal end of the sleeve. A syringe with filler material is slid overthe guide rail and attached to the proximal end of the filler tube. Thesurgeon then ejects filler material into the filler tube and thence intothe sleeve. He can withdraw the filler tube along the length of thesleeve until an adequate tissue augmentation profile is achieved. Thefiller tube is then removed from the sleeve along the guide rail,allowing the valve at the proximal end of the sleeve to close. If moreaugmentation is desired, the filler tube may be again passed over theguide rail, through the valve and into the sleeve, where more fillermaterial may be deposited. When the desired amount of filler material iswithin the sleeve, the filler tube is removed and the guide rail is cutflush with the skin at the proximal and distal ends of the sleeve. Thatportion of the guide rail within the sleeve remains there after thedistal and proximal ends are cut.

In an alternative embodiment, one or more stay sutures may also beattached to the proximal end of the sleeve. In use, the stay sutureextends from the proximal end of the sleeve and out to the externalaspect of the tissue. The surgeon may then grasp these stay sutures toprovide counterforce as the filler tube is advanced. In addition, thesurgeon may grasp the stay sutures and the distal suture, or distal staysutures if such are provided, in order to move the tissue filling deviceback and forth within the tissue to achieve optimal positioning. Whenthe desired amount of filler material is within the sleeve, the guiderail is cut flush with the skin at the proximal and distal ends of thesleeve, and the stay sutures are similarly cut close to the skin at theproximal end. The stay and guide sutures are ideally of bioresorbablematerial as are well known in the art.

In one embodiment, the grasping means for positioning the tissueaugmentation device comprises a suture, as described above. Other typesof grasping means can also be used in accordance with severalembodiments of the invention. In another embodiment, the grasping meanscomprises one or more tabs or flatted areas. In one embodiment, aportion of at least one membrane is flattened to provide thepractitioner with an uninflatable area for grasping. One advantage ofsuch an embodiment is that it may reduce the risk of damage (such as apuncture) to the inflatable portion of the augmentation device byminimizing direct contact with the inflatable portion. In oneembodiment, the flattened portion or tab comprises one or more layersthat are sealed using glue or another adhesive. In one embodiment, theflattened portion, or tab, is made of the same material as at least oneof the membranes of the augmentation device. In another embodiment, theflattened portion, or tab, is made of a different material than amembrane of the augmentation device. The flattened portion, or tab, canbe made of any shape suitable for grasping by a practitioner. In someembodiments, the tissue augmentation devices comprises a single tab. Inother embodiments, the tissue augmentation devices comprises two tabs.In yet other embodiments, more than two tabs are provides. A tab may belocated in any location that facilitates grasping by a practitioner. Ina preferred embodiment, the tab is located at the proximal and/or distalend of the augmentation device.

In an alternative embodiment and method of use, the tissue fillingdevice is implanted in the tissue to be augmented by means of an outerneedle or cannula. The needle has a proximal end and a distal end, and alumen extending from one end to the other. In one embodiment, the needleis 14-20 gauge. Thus, in one embodiment, the device to be implantedaccording to any of the embodiments described herein (e.g., the devicein its first configuration or uninflated state) is sized to fit througha 14-20 gauge needle or other tubular access channel. A 14-20 gaugetubular access channel translates into a tubular access channel havingan outer diameter of about 0.083 inches and an inner diameter of about0.063 inches (14 gauge) to a tubular access channel having an outerdiameter of about 0.0355 inches and an inner diameter of about 0.024inches (20 gauge). Thus, the device to be implanted, in someembodiments, has a pre-implantation diameter in the range of about 0.024inches (about 0.61 mm) to about 0.063 inches (about 1.6 mm). In oneembodiment, the device pre-implantation or pre-inflation has diameterless than about 1.6 mm. In alternative embodiments, the devicepre-implantation or pre-inflation has diameter greater than about 1.6mm. These latter embodiments need not be delivered through a 14-20 gaugeaccess channel.

In one embodiment, a sleeve assembly comprises the collapsed sleeve,valve and filler tube as described above. Optionally, a central guiderail may be supplied. The sleeve assembly is contained within the needlelumen such that the distal end of the sleeve assembly ends proximally ofthe distal end of the needle lumen. The filler tube runs through thesleeve and emerges at the proximal end of the needle, and then connectedto a syringe containing the filler material. If a central guide rail isprovided, the filler tube is adapted to ride over said rail. The fillermaterial can be any of those previously described. In one embodiment,stay sutures are provided attached to the proximal end of the sleeve andemerge through the proximal end of the needle. In use, the surgeonadvances the needle along the path in the tissue to be augmented from aproximally located entry site. The surgeon may put manual traction onthe tissue in order to guide the needle along the desired path. Thefiller tube is advanced within the interior of the sleeve, and along theguide rail of such is provide, until the distal end of the filler tubeis located at or near the distal end of the sleeve. The needle may beadvanced through the tissue and then emerge from the skin at a distallylocated exit site, or the needle advancement may stop within the tissuewithout an exit site. In either case, once the needle is in the desiredposition, forward tension is placed on the filler tube to keep thecollapsed sleeve in position, while the needle is retracted proximallyout of the tissue. The surgeon then ejects filler material into thefiller tube and thence into the sleeve. He can withdraw the filler tubealong the length of the sleeve until an adequate tissue augmentationprofile is achieved and may re-advance the filler tube distally ifrequired. The filler tube is then removed from the sleeve, allowing thevalve at the proximal end of the sleeve to close. If more augmentationis desired, the filler tube may be again passed through the valve andinto the sleeve, and over the guide rail if one is provide, where morefiller material may be deposited. When the desired amount of fillermaterial is within the sleeve, the filler tube is removed and any guiderail and any stay sutures are cut flush with the skin at the proximaland distal ends of the sleeve.

In one embodiment, the sleeve may take the shape of the upper lip in a“cupid's bow” configuration, with the valve and filler tube assembly asprovide above. The sleeve of this upper lip shape is also configurablefrom a first, collapsed state, to an expanded state. The sleeve of thisupper lip shape may be placed within the tissue either using thesew-through method or the outer needle method described above. In thisembodiment, the sleeve is generally 3 to 6 cm in length, 1 to 6 mm inwidth and 1 to 3 mm in depth. The upper edge has a flat “M”configuration to match the upper vermillion border of the lip. Thesleeve may be constructed of two sheets of any of the biocompatiblematerials describe above, preferably ePTFE, attached to each other, suchas by an adhesive of thermal cintering, along their edges.

In another embodiment, the sleeve is adapted to be placed in the cheekto enhance the malar fossa. In this embodiment, the shape and dimensionsare well known in the art, such as described for silicone implantsavailable from McGhan Medical Corporation, a division of Inamed. In onepreferred embodiment, the sleeve is approximately ovoid and constructedof two sheets of ePTFE sintered together at their outer edges, such thatthe sleeve, when in its inflated state, has dimensions of 4 to 6 cm inlength, 3 to 4 cm in width, and 0.3 to 1.5 cm in thickness in the centerof the sleeve, with the thickness tapering towards the edges.

In one embodiment, the device is compartmentalized and the compartmentsare adapted to be filled separately in order to vary the contour of thefilled region. In some embodiments, certain compartments are leftunfilled or partially filled, and may be filled at a later date toachieve or alter a particular contour. In one embodiment, the device hastwo or more compartments (e.g., 3, 4, 5, 5-10, 10-20, or more than 20compartments). As described in more detail below, these compartments canbe divided by one or more interior septums. These interior septums canbe pierced to inject filler and are re-sealable after a fill tube hasbeen removed. Alternatively, each compartment (which may or may not beseparated from other compartments by an interior septum) can be accessedfrom the exterior. Thus, the exterior can be pierced to provide fillerto one or more of the compartments, which then re-seals (with or withoutexternal intervention) after a fill tube has been removed. In thismanner, a practitioner can selectively fill some or all of the differentcompartments. The compartments can be of any size or shape (e.g.,square, rectangular, circular, ovoid, elongate, triangular, amorphous,etc.). In one embodiment, the compartments are substantially flat. Thus,in one embodiment, the device for implantation into the cheek (or othersuitable location) has a width of less than 3 mm. In other embodiments,the thickness is in the range of about 3 to 15 mm, as described above.In yet other embodiments, the thickness is greater than 15 mm.

In another embodiment of the invention, there is provided a tissueaugmentation device comprising a generally sheet like structure formedby opposing sheets or walls joined together internally to form multiplechambers in the device. The chambers are selectively fillable,completely or partially, so as to enable the device to be shaped to adesired overall contour. The walls comprise a material that isself-sealing, so that upon withdrawal of a filling means from anychamber that chamber is self-sealed to retain the filler therein. Ifdesired, the contour of the device may even be changed after filling oneor more of the chambers by extracting filler there from.

Preferably, in this embodiment, the device comprises a pair of sheets ofsuch self-sealing material closed together around their periphery. Suchclosure can be achieved by any suitable means, such as by heat orchemical bonding. More preferably, the sheets are similarly bondedtogether in any desired pattern to form multiple chambers orcompartments.

In a preferred embodiment, either each or both of the opposing walls ofthe sheet device may be formed from a laminate of a plurality of layers.

The sheet, which may have self-sealing properties in a preferredembodiment, are preferably made of ePTFE and/or polyurethane.

In a related embodiment there is provided a tissue augmentation devicecomprising a generally sheet like or substantially planar structurecomprising opposing, substantially planar walls joined together bybonding or inner walls to form a plurality of chambers therein.Preferably this embodiment has the characteristics described above. Morepreferably, the sheet comprises a plurality of inner chambers in anamount generally more than is needed by a surgeon for a particularapplication. In this embodiment, the surgeon can cut between thechambers so as to produce the desired shape and number of chambers for aparticular application.

The sheet or planar chambered embodiments are particularly suitable forfacial reconstructive surgery and the like.

In another embodiment, the sleeve adapted to be placed in the cheek hasthe dimensions described above, but additionally contains a length ofNitinol wire or ribbon in its superelastic state, of approximately 0.003to 0.030 inches in diameter, which is affixed within the edges along thecircumference of the sleeve between the sheets of ePTFE, which make upthe sleeve, using a thermoplastic adhesive such as FEP or polyethylene.In such an embodiment, the sleeve is assisted in expanding from itsfirst configuration to its second configuration, and maintaining itsshape in the second configuration, by the shape memory properties of theNitinol.

In similar fashion, other embodiments of a sleeve in the size and shapeadapted to be used as tissue augmentation implants in the dorsum of thenose, the chin, the region under the eyes, the breast, or any anatomiclocation clinically indicated may be constructed in the fashiondescribed above either without or with the support of a Nitinol framestructure.

Certain specific implementations of the invention will be described withreference to FIGS. 1-12. Referring to FIG. 1, there is illustrated aschematic representation of a tissue augmentation implant in accordancewith one aspect of the present invention. The implant comprises a sleeve10, having a proximal end 12 and a distal end 14. Sleeve 10 may beeither an empty sleeve with a single or plurality of macro compartments,or the outer surface of an open cell or closed cell foam as has beendisclosed elsewhere herein.

The sleeve 10 comprises a body 16, which, in the present embodiment,defines a central cavity 18. The body 16 is additionally provided with adistal port 20, which is in communication with a proximal port 22 by wayof a lumen extending therebetween. In the illustrated embodiment, thedistal port 20 is on a distal end of the body 16 and the proximal port22 is on the proximal end of the body 16. However, either port may bepositioned along the length of the body 16 spaced apart from therespected end, depending upon desired performance and other designconsiderations. A plurality of ports may also be desirable.

In the illustrated embodiment, the distal port 20 and proximal port 22serve as guidewire access ports to allow the body 16 to be slideablyadvanced along a guidewire 24.

The illustrated ports 20 and 22 are in communication with each other byway of the central cavity 18. However, a separate lumen may be providedthrough the sleeve wall or on the outside of the sleeve if it is desiredto isolate the guidewire lumen from the filler media.

As has been discussed herein, the body 16 is transformable from areduced cross sectional configuration such as for positioning at adesired treatment site, to an enlarged cross sectional configuration forproviding a desired cosmetic result. In one embodiment, illustratedschematically in FIG. 2, the body 16 is transformed to the enlargedcross sectional configuration by filling the central cavity 18 with anyof a variety of desired filler materials 30. A filler tube 26 isadvanced along the guidewire 24 to position a fill port 28 within adesired portion of the central cavity 18. The proximal end of the fillertube 26 (not illustrated) is connected to a source of filler media, suchas a hypodermic needle syringe or other container depending upon thenature of the filler media. Suitable filler materials are disclosedelsewhere herein, and the nature of the filler tube may be modified totake into account the nature of the filler as will be apparent to thoseof skill in the art in view of the disclosure herein.

The filler tube 26 may be advanced throughout the length of the sleeve10 into the vicinity of the distal end 14. Filler 30 may be deployedthrough the fill port 28 by activation of a fill control (notillustrated) on the proximal control. The filler tube 26 may be axiallyproximally retracted through the sleeve 10 to introduce filler 30 atdifferent positions along the length of the sleeve. After a sufficientamount and desired distribution of filler 30 has been introduced intothe sleeve 10 to achieve the desired result, the filler tube 26 may beproximally retracted from the proximal end 12, and removed from thepatient. See FIG. 3. Proximal end 12 may be provided with a valve 32 ashas been described herein, to permit removal of the filler tube 26 andretention of the filler media 30 within the sleeve 10. The guidewire 24may also thereafter be proximally withdrawn from the sleeve 10, therebyleaving the filled implant in position at the desired treatment site.

For certain applications, the sleeve 10 is preferably fillable to anon-uniform profile. This may be accomplished utilizing the embodimentof FIGS. 1-3, together with a filler which has sufficient viscosity, orstructural characteristics (e.g. wire coils) that the filler will remainat a localized position within the sleeve 10. Alternatively, referringto FIG. 4, there is illustrated a segmented embodiment of the invention.The sleeve 10 is divided into a plurality of segments 34, which areseparated by a plurality of neck portions 36. The fill port 28 on thefill tube 26 may be sequentially positioned within each of the segments34, to allow each segment 34 to be inflated to a unique cross sectionaldimension. In this manner, the cross sectional dimensions of the implantare customizable along the length of the implant as may be desired toachieve a desired cosmetic result.

The neck portion 36 may be formed in any of a variety of ways, such asby heat forming the sleeve 10, or by placing any of a variety ofstructures such as a band around the neck portion 36. Referring to FIG.5, the segmented implant is illustrated with a filler tube 26 in placewithin a segment 34. Adjacent segments 34 are separated by a restriction37 such as an annular elastic band or gasket. The restriction 37 hassufficient elasticity to permit passage of the filler tube 26, butrecoils back to close of substantially close the passageway betweenadjacent segments 34 following removal of the filler tube 26. Thus, therestriction 37 may be configured to either restrict and control flowbetween adjacent segments 34, or completely block flow of filler 30between adjacent segments 34.

The nature of the restriction 37 in neck portion 36 is configured tocooperate with the nature of the filler 30 as will be appreciated bythose of skill in the art in view of the disclosure herein. For example,the restriction 37 need not provide a rigorous seal if the filler 30comprises a plurality of coils, fibers, or particular material. However,if a less viscous or more flowable filler 30 such as saline solution isutilized, restriction 37 should be configured to provide a seal betweensegments 34 if it is desired to prevent flow of filler 30 betweenadjacent segments 34. Optimization of these parameters may be achievedthrough routine experimentation by those of skill in the art, takinginto account the desired clinical performance of the implanted device.

Referring to FIG. 6, a sleeve having a plurality of internal baffles 40is disclosed. Baffles 40 function to divide the interior cavity 18 ofthe sleeve 10 into a plurality of chambers or compartments 38, withoutnecessarily influencing the external profile of the implant. Similar tothe restriction 37, baffles 40 permit the filler tube to be advanced andretracted to reach each compartment 38, and then to prevent or tosubstantially prevent the flow of filler 30 between adjacentcompartments depending upon the desired clinical performance. As afurther alternative, the baffles 40 or valves may be in the form of apierceable septum, which permits passage of the fill tube 26 but whichreseals either completely or substantially following removal of thefiller tube 26. Alternatively, each chamber or compartment (which may ormay not be separated from other compartments by an interior septum) canbe accessed from the exterior. Thus, the exterior can be pierced toprovide filler to one of the compartments, which then reseals (with orwithout external intervention) after a fill tube has been removed. Inthis manner, a practitioner can selectively fill some or all of thedifferent compartments to achieve a desired profile or contour.

Referring to FIG. 7, there is illustrated one embodiment of a fillertube 26 in additional detail. Filler tube 26 comprises a proximal end50, a distal end 52 and an elongate tubular body 54 extendingtherebetween. Tubular body 54 may be flexible or rigid, depending uponthe desired performance. Tubular body 54 may be formed in any of avariety of ways, such as by machining from metal components (e.g.stainless steel hypotube) or by extruding any of a variety of polymericmaterials well know in the catheter arts, such as PEEK, PEBAX, variousdensities of polyethylene, among others.

The tubular body 54 includes at least one central lumen for receivingthe guidewire or guide rail 24 therethrough. The guidewire lumen is incommunication with a guidewire access port 58 on the proximal manifold56. Proximal manifold 56 is additionally provided with a filler port 60,which may be a lure connector or other quick release hub, for removableconnection to a source 62 of filler 30. In one convenient embodiment,source 62 is in the form of a manually activatable syringe.

The tubular body 54 may be provided as a dual lumen structure, havingeither concentric or side-by-side lumens as is well known in thecatheter arts. Alternatively, depending upon the nature of the filler30, the guide rail 24 may extend through the same lumen as the fillermedia as well be appreciated by those of skill in the art in view of thedisclosure herein.

Although the filler tube 26 is illustrated as having a single effluentport 28 for introducing filler 30 into the sleeve 10, a plurality offiller ports 28 may be provided. In addition, the filler port 28 may bethe same as the distal opening through which the guide rail 24 extends.In an embodiment having multiple effluent ports 28, the multiple portsmay be arrange circumferentially in a single transverse plane about thetubular body 54, or may be spaced axially apart along the length of thetubular body 54 such as for use in a procedure where it is desired tofill multiple compartments 38 simultaneously.

A further implementation of the invention is illustrated in FIG. 8. Aschematically illustrated sleeve 10 extends from a proximal end 12 to adistal end 14. The sleeve comprises a flexible body 16 which maycomprise an outer fabric sleeve or the outer surface of a segment offoam, as has been discussed elsewhere herein. In the illustratedembodiment, the body 16 defines at least one central cavity 18, having aproximal port 22. Proximal port 22 is provided with a valve 32, forsealing the central cavity 18 following introduction of filler material30 and removal of the filler tube 26.

In the implementation of the invention illustrated in FIG. 8, the distalend 14 of the sleeve 10 is provided with a closed end. A distal suture70, extending from a proximal end 72 to a distal end 74 is attached tothe closed distal end 14 of the sleeve 10. In alternative embodiments,distal end 14 may be provided with an open access port, with or withouta valve, depending upon the desired filling configuration. The suture 70may also extend throughout the length of the sleeve 10, and proximallyfrom the proximal end 12 of sleeve 10, depending upon the desiredperformance.

In the illustrated embodiment, the distal suture 70 extends from thedistal end 14 of the sleeve 10, to a needle 76 attached to the distalend 74 of the suture 70. Needle 76 may comprise any of a variety ofsewing needles, as will be apparent to those of skill in the art in viewof the disclosure herein.

FIG. 9 schematically illustrates the use of the embodiment of FIG. 8.The needle 76 is introduced into the skin 73 at a first access point 75.The needle is advanced subcutaneously beneath an area to be treated.Needle 76 is thereafter advanced through the surface of the skin at anexit point 77. Further traction on the needle 76 and suture 70 pull thetubular sleeve 10 through the entrance point 75 and into positionbeneath the region of skin to be treated. Once the sleeve 10 is in thedesired position, the filler material 30 is advanced from a source intothe central cavity 18. Following introduction of a desired volume offiller material 30, the filler tube 26 is proximally withdrawn from thesleeve 10, and the distal suture 70 is severed at or below the skinsurface.

Referring to FIGS. 10 and 11, there is illustrated an embodiment likethat in FIGS. 8 and 9, with the added feature of a proximal stay suture78. Proximal stay suture 78 may be attached to the sleeve 10 in thevicinity of the valve 32, or may be a continuous suture with the distalsuture 70, extending along the outside or the inside of the body 16.

In use, the proximal stay suture 78 and the distal suture 70 may be usedto manipulate the sleeve 10 along its axis to optimize positioningeither before, during or following introduction of filler material 30into the central cavity 18.

A schematic representation of the use of an external introduction needleis illustrated in FIG. 12. In the present context, the use of the term“needle” is not intended to imply any specific structural dimensions,other than as necessary to provide access for subcutaneous insertion ofthe implant. The actual dimensions of the introduction needle will beoptimized for or governed by the configuration of the implant and fillertube as will be apparent to those of skill in the art.

Placement needle 82 comprises an elongate tubular body 83 extendingbetween a proximal end 84 and a distal end 86. Tubular body 83 comprisesan elongate central lumen 88 extending therethrough. The tubular body 83may comprise any of a variety of forms, depending upon the intendedclinical use. For example, tubular body 83 may comprise a straight, acurved, or a flexible configuration. Typically, the distal end 86 willbe provided with a bevel or other sharpened tip, to facilitate advancethrough soft tissue. Depending upon the diameter of the tubular body 83,a separate obturator tip may be positioned within the tubular body 83 tofacilitate positioning of the tubular body 83 in the desired treatmentsite. The obturator may thereafter be removed, and the sleeve 10advanced into position within the tube.

In the embodiment schematically illustrated in FIG. 12, the tube 83 hasa sufficient inside diameter to accommodate a proximal hub 90 on thefiller tube 26. This allows the placement needle 82 to be proximallyretracted over the assembly of the sleeve 10 and filler tube 26following placement at the treatment site. Alternatively, the placementneedle 82 can be configured to be withdrawn in a distal direction out ofthe exit point 77 (see FIG. 9). Thus, depending upon the desiredclinical performance, the placement needle 82 may be proximallyretracted or distally advanced off of the sleeve 10. In an alternateconfiguration, placement needle 82 may be in the form of a peel-awaysheath, which can be removed proximally without the need for an insidediameter sufficient to accommodate the proximal hub 90. Any of a varietyof configurations may be utilized for the placement needle 82, as willbe apparent to those of skill in the art in view of the disclosureherein.

Referring to FIGS. 13A through 13D, there is illustrated a manufacturingsequence for a tissue augmentation device in accordance with the presentinvention. 13A illustrates a tubular sleeve 100 which extends between aproximal end 102 and a distal end 104. A central lumen 106 extendstherethrough. Tubular sleeve 100 may comprise any of a variety ofmaterials such as ePTFE and others described elsewhere herein. Ingeneral, tubular sleeve will have a sufficient length and diameter toaccommodate the desired treatment site. For treatment of wrinkles in theface, tubular sleeve 100 will generally have a length within the rangeof from about 1 cm to about 6 cm, and a diameter within the range offrom about 1 mm to about 8 mm. The wall thickness of the tubular sleeve100 may also be varied considerably, but will often be within the rangeof from about 0.003 to about 0.020 inches.

Referring to FIG. 13B, there is illustrated the first step inconstruction of the proximal valve 114. A biasing element 108 such as anelastic band, suture, spring biased metal clip, or other clamp orbiasing member is positioned around the tubular sleeve 100 to create aneck, spaced slightly apart from the proximal end 102 leaving a trailingend 110 of the tube 100. The biasing element 108 is preferablysufficiently tightly positioned around the tube 100 to provide asuitable seal taking into account the desired filler material as hasbeen discussed.

As seen in FIG. 13C, the tubular body 100 is then turned inside out(everted) so that the trailing end 110 is positioned within the centrallumen 106. The biasing element 108 is also positioned within the centrallumen 106, presenting a valve opening 114 on the proximal end 102 of thetubular body 100. Valve opening 114 permits the introduction and removalof a filler tube as has been discussed.

Referring to FIG. 13D, a distal closed end 120 is formed on the tube100. Closed end 120 may be provided in any of a variety of ways, such asby one or more loops of a suture 118 which may be tied into a knot.Alternatively, any of a variety of adhesives, thermal welding,elastomeric bands, clips or other biasing structures such as thoseutilized to form valve 114 may be used. In the illustrated embodiment,closed end 120 is provided by tying a suture tightly around the distalend 104 of the tube 100. A trailing end 116 of the suture is leftattached to the suture knot, to provide assistance during positioning ashas been discussed. The distal suture 116 may thus be provided with asewing needle (not illustrated) for percutaneous introduction into thetreatment site.

Referring to FIG. 14, there is illustrated a tissue augmentation deviceas in FIG. 13D, with an optional guidewire 122. Guidewire 122 extendsthrough the valve 114, and at least as far as the distal closed end 120.Guidewire 122 may be permanently attached, at the closed distal end 120,or may be removable such as by proximal traction depending upon thedesired clinical performance. In one embodiment, the guidewire 122 issecured within the suture knot 118 and not intended for removal. In thisembodiment, following placement and filling of the implant, the proximalportion of guidewire 122 is severed at about the valve 114. Guidewire122 may comprise any of a variety of filaments, such as a suture, or ametal wire such as stainless steel or Nitinol. As has been discussed,guidewire 122 may provide assistance in axial repositioning orpositioning of the filler tube, which may be advanced over the guidewire122 and into the tubular sleeve 100.

Various embodiments of implants disclosed therein, both of a generallycylindrical form and of a generally sheet-like form, may be implanted inseveral locations throughout the body. Some specific possible implantlocations on the face are illustrated in FIG. 15 below.

Referring to FIG. 15, implants of the disclosed design are also usefulin the periorbital region, such as the suborbital rim 210, including themore medial portion of the suborbital zone known as the tear trough 216.Depending on physician preference and patient anatomy, an implant forthis location can be similar to either the elongate, generally linearimplants such as those used for the nasolabial region 200, or can be ofa more sheet-like planar nature and extend inferiorly to the region inwhich the malar prominence meets the cheek or medially to the region inwhich the malar prominence meets the nose (the nasojugal region).

Wrinkles in the glabellar region 212 can be corrected with an implant ofthe disclosed design as well. As described in reference to theperiorbital region, the particular anatomy of this region and physicianpreference will determine whether a linear or planar implant is bestsuited, as either can be effective for the types of defects or wrinklesfound in this region.

In another embodiment, the bridge of the nose 214 can be augmented witha planar-type implant of the disclosed design. Use of such an implantcan be particularly effective in patients who have a flattened nasalbridge but desire a more prominent nasal bridge.

In one embodiment, augmentation of the malar and submalar regions 218 byuse of an implant of the disclosed design can be very effective inreshaping a patient's face through the alteration of the underlyingstructure on which the overlying soft tissue is draped. Implants in thislocation would benefit from use of the disclosed self-sealingchronically adjustable membrane, as would all of the other implantsdescribed herein. FIG. 16 is a plan overhead view of a deflated mid-facemalar implant, while FIG. 17 illustrates the same implant in inflatedcondition. Both figures illustrate an embodiment with a plurality ofinternal segments 21, which may be separated by a series of valves orbaffles 23 (e.g., seams formed by thermal bonding, adhesives, etc.)described above. Furthermore, a planar implant may also be used in thetemporal region 220.

FIG. 18 shows cross-sections of various preferred tube-based andsheet-based implants in various configurations that can be utilizeddepending on the desired implant location, specific contours of thepatient's face, and physician preference. FIG. 18A illustrates theconfiguration of a tube-based, taut-filled implant. FIG. 18B shows atube-based, slightly flaccid implant. FIG. 18C shows a tube-basedmarkedly flaccid-filled implant. FIG. 18D shows a sheet-based,taut-filled implant. FIG. 18E discloses a sheet-based, flaccid filledimplant. FIG. 18F shows an example of a sheet-based implant with twosheets of differing compliances (or two sheets of similar compliance butdissimilar area) that may be desirable in order to make an asymmetriccross-section upon inflation. Sheet layer 224 shown is desirablyconstructed of, for example, a relatively low modulus elastomeric filmthat is highly compliant, producing a more curved shape. Sheet layer226, in contrast, may be made of a relatively higher modulus, lesscompliant elastomer/polymer. The sheet-based implants may all use bondedseams 222 to connect the two sheet layers together.

In one embodiment, an implant 200 (FIG. 15) that is of an elongatenature may have a cross-section that is either substantially round or aflattened shape (when flaccidly filled) as previously disclosed, andillustrated in FIGS. 18A-C. Alternatively, the implant may beconstructed using a sheet-based method to product cross-sections such asthose shown in FIGS. 18D-F. Such an implant is well suited to effacementof the nasolabial groove. A similarly shaped but shorter implant 202 canbe used for the marionette lines (or “pre-jowl sulcus”). In both ofthese cases, the implant is used to augment the soft tissue that liesbeneath a line-like feature in the patient's skin, commonly referred toas a wrinkle or rhytid. Similarly, implants of this type will beeffective at any of the locations shown in FIG. 19, illustrating theterminology and anatomical location of typical sites of facial wrinkles.Length, diameter, cross-sectional shape and overall shape, such aswhether the elongate shape is linear or arcuate, bulbous, tear-dropshaped or otherwise curved, are ideally chosen to best suit each ofthese locations. Alternatively, many of the wrinkle locations on manypatients may be effectively effaced through the use of an implantselected from a kit which includes a relatively small number (e.g. atleast about three or four and often no more than about 5 or 10) of moregenerically shaped implants that are made available in incrementallengths and diameters.

In another embodiment, a deeper implant 204 can be used for the severallocations in the chin (mental) region or other portions of the mandible.The implant will have a curved shape if used to augment the centralmentum in order to match the natural curvature of the bone, but is lesscurved if used to augment the posterolateral mandible 206 also referredto as the angle of the mandible or the pogonion. Implants such as thiswill generally be formed using sheet-based methods and be implanted at arelatively deep tissue plane, such as just supraperiosteal orinfraperiosteal (just on or below the outer surface layer of the bone).In some cases, however, physicians may, depending on aesthetics and theunique characteristics of the patient choose to place these implants inthe same subdermal plane used for the wrinkle-correcting implants suchas those described above.

Also disclosed in the present invention is a tissue augmentation devicespecially tailored for nasolabial implantation. The method ofimplantation, as well as a specialized grasper to assist inimplantation, will also be described. In this embodiment, there is atissue augmentation device with size and shape that is preferred forplacement below the nasolabial area of a patient's face in order toefface the crease-like appearance of that area. Other sizes and shapesmay be preferred for other facial zones as described below. FIG. 20shows one embodiment of an inflatable tubular implant in its deflatedstate as it would be seen prior to insertion into the soft-tissue (suchas the nasolabial region) of a patient. The body 130 of the implantconstitutes the central portion and is responsible for the majority ofthe volume augmentation that the inflated implant provides. A distal tab132 is provided to allow for insertion and manipulation of the implantwithout directly grasping or otherwise attaching to the implant body. Inthis embodiment, “distal” refers to that end being farther away from thetypical point of entry. In the case of the nasolabial area, the distalend of the implant will typically be positioned in the perialar zone(near the patient's nostril) and will thus also be referred to as thesuperior or cranial ends.

In one embodiment, also shown in FIG. 20, the distal tab 132 is providedwith a through-passage such as a punched hole 136 which allows passageof a suture 134. The hole 136 may be provided with a reinforcementstructure, such as a metal or polymeric ring to reduce the risk of thesuture pulling through the distal end of the tab 132. Alternatively, afilament such as a wire can extend axially along a first side of theimplant, loop around the distal side of the hole 136 and then extendaxially along a second side of the implant. Alternative reinforcingstructures may also be used.

The suture 134 may be formed into a loop as shown here or may passthrough the tab and then be knotted in typical fashions. The suture 134allows the physician, who may also be an assistant, or other operator,to apply traction to the distal end of the implant for purposes ofeither providing location and orientation control during and after theimplantation procedure, drawing the implant into the tissue to implantit (in what is referred to as the “sew-through” method), or both. Thesuture 134 connects on its other (distal) end, not shown, to either asurgical needle or to a delivery system which may combine needleelements with other delivery system elements, such as dissectioncomponents for sharp dissection, blunt dissection or both.

The distal tab 132 meets the body of the implant 130 along a generallyarcuate path, said path being formed during the fabrication process bycontrolled application of adhesive, heat-bonding or other suitablebonding means, under compression using a curved tool. The generallycircular path of the edge of the bond causes the implant to inflate atits distal end into a bulbous shape. This design is advantageous in thatit more closely matches the required tissue augmentation of this regionof the nasolabial area: the subdermal tissue plane in which the implantis optimally placed is at its deepest in this location relative to therest of the nasolabial region, from approximately 2 mm to 6 mm deep tothe skin, and the depth and extent of the nasolabial crease (which canalso be referred to as the nasolabial fold or the nasolabial sulcus) isat its greatest in this location. A distal tab 132 may have an axiallength of at least about 1/16″, ⅛″, ¼″, ½″, or more, and may furtherenable grasping by a grasping tool, described further below.

In another embodiment, a proximal tab 140, with or without a reinforcingelement may be provided as well to allow further locational andorientational control of the implant during and after the implantationprocedure. The proximal tab 140 also provides a fixation zone for thevalve assembly 138, which may be fixated to the inside materials of theproximal tab 140 by adhesive, heat-bonding or other suitable bondingmeans. A proximal tab 140 may have an axial length of at leastapproximately 1/16″, ⅛″, ¼″, ½″, or more to enable grasping by agrasping tool, described further below.

The most proximal portion of the valve assembly is the neck tube 144into which the fill tube 142 is inserted. FIGS. 21A and 21B illustratethe components of the valve assembly. The valve assembly consists of aneck tube 144 surrounded by an elastomeric valve tube 141 or otherspring-like material such as stainless steel, spring steel orsuperelastic NiTi. Positioned within the elastomeric tube 141 andadjacent the tube 144 is a valve plug 143. In FIG. 21B, an exaggeratedcross-sectional view of the valve assembly (to show the functionalrelationship between the valve plug 143 and neck tube 144, a cylindricalvalve plug 143 positioned within an outer sleeve of the valve tube 141,causes the neck tube 144 to collapse in a “crescent-moon” shape inresponse to the inward radial constriction of the valve tube 141.Without the valve plug 143, the neck tube 144 would constrict insphincter-like fashion thus allowing leakage along the small foldsinherent in that type of collapse. The valve plug 143 may contain orcomprise filler material 500 such as compressible foam or an elastomericrod holding the valve tube collapsed unless the filling cannula is inposition therein.

Depending on the desired long-term performance of the valve assembly, itmay be desirable to add an additional sealing component, such as anitinol or stainless steel, clip or a seal by heat sealing orapplication of an adhesive after filling, to maintain the competency ofthe valve. Some additional sealing components are depicted in FIGS.21C-G. FIG. 21C is a valve with a nitinol coil restraint 501, while FIG.21D is another valve 144 with a nitinol coil restraint 501 in adifferent configuration, according to one embodiment of the invention.FIG. 21E is a valve 144 with a “paper clip” configuration of the nitinolcoil restraint 502, while FIG. 21F is another variation of a nitinolcoil restraint 502, according to another embodiment of the invention.Another alternative embodiment of an additional sealing mechanism isshown in FIG. 21G, a valve 144 with a folded O-ring 503 configuration.Any other variety of additional steps such as sealing, clamping,locking, gluing, radiofrequency welding, or ultrasound may also beutilized. Furthermore, in another embodiment, a thermal source such aslaser, electricity, flame, or a heating loop may be utilized to melt thevalve shut, such as a flange with a wire loop attached to the fill tubeand proximally connected to a power source, such as a battery.

FIG. 22 shows an embodiment of the same implant of FIG. 20 after it hasbeen inflated and after the fill tube has been removed and theself-closing valve assembly has closed to maintain the inflation of theimplant. Typically, the implant is inflated with saline, although othermaterials can be used as well as previously described. The distal taper146 forms a generally hemispherical or bulb-like shape while theproximal taper 148 forms a more flattened, triangular shape. Theadvantage of the distal taper shape was described above. The proximaltaper 148 inflates to a more flattened shape because the edge of thebond that separates the proximal taper 148 from the proximal tab of theimplant follows an arcuate path or other geometry perimeter line that iselongated axially relative to the arcuate path of the edge of the distaltab. As a result, the distance, measured in an axial direction, betweenthe proximal limit 148A and the distal limit 148B of the distal edge ofthe proximal bond is greater than the corresponding axial distance onthe distal end of the implant. The proximal bond edge length isgenerally at least about 110%, often at least about 150% and can be atleast about 200% of the axial length of the distal bond edge. Thus theimplant can not inflate as fully in the direction perpendicular to theplane of the tab at a comparable distance from the end of the tab. Thisdesign is advantageous in that it more closely matches the requiredtissue augmentation of this region of the nasolabial area: the subdermaltissue plane in which the implant is optimally placed is at its mostsuperficial in this location relative to the rest of the nasolabialregion, from approximately 1 mm to 4 mm deep to the skin, and the depthand extent of the nasolabial crease (which can also be referred to asthe nasolabial fold or the nasolabial sulcus) is at its minimum in thislocation.

The dimensions of a preferred implant are as follows. The inflated axiallength may be from about 1-15 cm, preferably about 1.5-8 cm, morepreferably about 2-5 cm. The diameter of an inflated implant may be fromabout 2-10 cm, preferably about 3-8 cm, more preferably about 4-6 cm.The maximal cross-sectional area of an inflated implant may be no morethan about 80 cm², preferably no more than about 50 cm², more preferablyless than about 30 cm², or even 12 cm² or less. In certain embodiments,it may be desirable to have a uniform diameter and cross-sectional areathrough the body of the implant. In alternative embodiments, thecross-sectional area may vary along the axial length of the implant,with at a first axial distance from an end there will be a firstcross-sectional area, and at a second axial distance from the end therewill be a second, different cross-sectional area. This secondcross-sectional area may be at least about 110%, 120%, 130%, or more ofthe first cross-sectional area. These alternative embodiments thus maycreate an implant that has, for example, a transition such as a uniformtaper, progressive curve, accelerated curve, and the like.

FIG. 23A is a cross-sectional view through the implant in the region ofthe distal taper 146. It is shown first in an embodiment in which thephysician has chosen to inflate the implant to its maximum recommendedinflation volume, which creates a soft, flaccid implant but is at thehighest end of the range of volumes that will create those soft, flaccidcharacteristics. At this fill-volume, the cross-sectional shape of theimplant in the main body section as well as in the distal taper regionis close to circular. For example, a preferred maximum fill volume of animplant may be in the range of from about 1-60 cc, preferably from about5-40 cc, 10-30 cc, or more preferably about 15-25 cc. A preferredflaccid-filled implant may be filled to about, for example, no greaterthan about 50%, 60%, 70%, 80%, or 90% of the maximum fill volume.

Also seen in FIG. 23A is the dual-layer construction of a preferredembodiment. An outer porous or textured material layer 150, such asexpanded polytetrafluoroethylene (ePTFE), porous polyethylene, texturedpolyurethane or textured silicone contacts the body tissues surroundingthe implant. The characteristics of these materials allow forincorporation of the implant into the tissue without encapsulation. Thisis due to controlled and slight cellular ingrowth that occurs with theproperly selected porous or textured material. One such material isePTFE with a pore size of between 30 and 100 microns, preferably between50 and 80 microns.

FIG. 23B illustrates an embodiment of an implant with variations inlamination, in which the porous outer material 150 is affixed to theunderlying inner elastomeric material 152 in wound or interruptedconfigurations, for example, helical, bands, stripes, and otherdiscontinuous patterns. These alternative embodiments are beneficial incontrolling the total surface area susceptible to tissue ingrowth andreducing capsule formation, such as when it is desired that the implantbe removed at a later date. The percentage of the total surface area ofthe implant which is provided with an outer porous layer can be varied,depending upon the desired clinical result. In general, although 100%coverage may be desired in certain circumstances, the outer porous layermay alternatively cover no more than about 90%, and in some embodimentsno more than about 75%, and in further embodiments no more than about50% of the total surface area of the implant. The configuration of theporous outer layer may also be varied, such that it may be positioned onend zones of the implant, positioned in a central zone on the implant,or distributed throughout such as by a spiral winding, spaced aparttransverse rings, checker board pattern, or otherwise.

When the porous layer is provided as a spiral winding, or as a series oftransverse circles surrounding the implant, the implant may more readilyexpand and contract in an axial direction, while maintaining a constantcross sectional profile. In general, the materials utilized for theporous layer (e.g. ePTFE) are less compliant than materials useful forthe inner layer. As a consequence, elongation of the implant as a resultof over inflation, or compression of one end of the implant will allowaxial stretching or expansion of the implant without being constrainedby the porous layer. This may among other objectives help provide anatural feel, upon manual palpation of the implant from the surface ofthe skin.

Within the outer layer 150 is an inner layer 152, which provides afluid-tight seal and, along with the valve assembly, enables the implantto be inflated and to maintain its inflation. This inner layer 152 ispreferably formed from an elastomer, such as dimethylsiloxane (silicone)or polyurethane, and more preferably from an elastomer with a durometerbetween about 40-00 and 80-A on the Shore hardness scales. This enablesthe implant to not only be soft and flaccid upon presentation of aninitial deforming force but to also have “cushioned stop” when thedeformation exceeds the amount that the flaccidity is able to absorb.This inner layer 152 of the implant can also be made of inextensiblematerials thus relying completely on its flaccidity in order to presentmechanical softness; this is particularly suitable in implant locationsthat are in deeper tissue planes, such as against the periosteum oragainst bone. The filler 154, is within the inner layer 152.

FIG. 23C is a cross-section of the embodiment of FIG. 23A in which thephysician has chosen to inflate the implant to a level below the maximumrecommended inflation volume. This creates a markedly flaccid implantthat even further conforms to the pocket with the tissue bed created bythe physician during implantation. This conformability and flaccidityallows the implant to “blend” with the surrounding tissue in terms ofits mechanical properties, and renders it very difficult to palpate. Thematerials of the implant are generally of an optically clear nature,particularly once in contact with body fluids, and the soft, flaccidshape does not cause it to impart a protrusion on the skin surface; thusthe implant is invisible to the eye and very difficult to detect bypalpation. Invisibility of detection to the eye and difficulty ofpalpation are desirable characteristics of implants in cosmetic andreconstructive surgery.

FIG. 23D shows a preferred nasolabial implant and various preferredcharacteristics. The implant contains both the inner layer 152 made ofpreferably silicone, and an outer layer 150 which may be made of, forexample, ePTFE. There is a proximal bonded zone D2 and distal bondedzone D3 shown shaded, where the inner layer 152 and outer layer 150 arebonded such as by the use of a silicone adhesive. The axial lengths D2and D3 may be identical, or may be different lengths in differentembodiments. Furthermore, there may be a central zone without bonding D1where the inner layer 152 and outer layer 150 can “slip” and allow forflotation of the inner layer 152 with respect to the outer layer 150. Adesirable implant will have compliance matching with the surroundingnative tissues to provide a more natural feel and appearance. Thisunbonded zone D1 allows for elongation of the ePTFE outer layerconstruct 150 as well as the inner layer 152 which will serve toincrease the compliance of the implant. The axial length D1 of theunbonded zone may be anywhere between about 0.5-14 cm, preferably about1-10 cm, 1.5-6 cm, and often between about 2-4 cm. The length D1 of theunbonded zone may be at least about 10%, 20%, 50%, 67%, 75%, or more ofthe overall implant length in some embodiments.

The implant is preferably impermeable or minimally permeable to vapor orliquid at physiologic temperatures. Depending on the desired long-termstability of the implant, it may be desirable to add one or moreadditional layers. This may be desirable, for example, to inhibitpermeability at physiologic pressures and temperatures, and thuspremature deflation.

FIG. 24A shows a cross-section of the proximal taper 148 of theembodiment of FIG. 22. Note the flattened cross-section that enables theproximal portion to better “feather” into the zone of the nasolabialgroove that is close the oral commissure. FIG. 24B shows the effect onthe proximal end of inflating the implant of the embodiment of FIG. 24Ato a level below the maximum recommended inflation volume, creating amarkedly flaccid implant with the same aforementioned advantages.

FIG. 25 illustrates the general shape of an advantageous nasolabialimplant in which the distal zone 158 is to the left and the proximalzone 166 to the right, according to one embodiment of the invention. Aspreviously described, it is advantageous for the distal zone 158 to begenerally bulbous while the proximal zone 166 is generally a flattenedtriangular taper. The general size of the implant can be characterizedby its diameter 162 which would be measured at the maximum recommendedinflation volume when the cross-section would be generally circular andwhich will characterize the middle zone 156 of the implant. The distaltapered zone 158 can be characterized by its radius of curvature 164based upon a best fit curve, which can be larger than one-half thediameter 162, thus creating a marked bulbuosity to the distal end zone158 of the implant. This may be advantageous in patients withparticularly deep nasolabial folds, especially in the perialar region.The proximal zone 160 is of a generally triangular shape within theplane of the proximal tab 140 and can be characterized by the length ofthe tapered zone 160 and the best fit radius of curvature of theinterior edge of the seam at the proximal tip 166. The length 160 is, ina preferred embodiment, between one-tenth and six-tenths the length ofthe middle zone 156. The length of the distal region 158 is, in apreferred embodiment, between one-tenth and six-tenths the length of themiddle zone 156.

The following is a preferred method of assembling a nasolabial implant,according to one embodiment of the invention. This method will produce apreferred 4.5 mm diameter implant with one tapered end, end laminationof silicone and ePTFE tubing, and 50% silicone tubing pre-stretch.Preferred implants constructed in this method are 2 cm, 3 cm, or 4 cm inaxial length when inflated.

The first step of assembling the nasolabial implant is to construct alamination subassembly. A piece of 0.160″ ID×0.004″ wall silicone tubing300, 50% stretch, is cut to a length of 2.90 inches. Next, the ePTFEtubing 304 is cut to a length of 4.5 inches. The silicone tubing 300 isthen slipped over the PTFE mandrel 302 until the proximal end of thesilicone tubing 304 is about 0.125 inches from the PTFE end, as in FIG.26A. Next, a piece of shrink tube ⅛ inch long is cut. The ePTFE tubing304 is then slid over the small diameter end of the mandrel 302, untilit is aligned with the silicone tube end, as in FIG. 26B. FIG. 26C showsthe shrink tube 306 placed over the end of the ePTFE tubing 304. Heat isthen applied, as in FIG. 26D, until the tube is shrunk down using a hotbox 308 set at a temperature of 335-345° F., more preferably 340° F.,and 35-45 SCFH. The shrink tube 306 is checked to ensure coverage ofboth the ends of the silicone 300 and ePTFE 304 tubing. Next, usinglubrication, preferably 99% isopropyl alcohol (IPA), the silicone tube300 is stretched until it reaches the distal end of the ePTFE mandrel302 and held in place using an O-ring 314 applied with an O-ringfixture, as in FIG. 26E. Then, silicone adhesive, preferably Med 2-4213,is applied to the surface of the silicone tube. Preferably, as in FIG.26F, adhesive is applied about 20 mm from one end of the PTFE coveredmandrel. Depending on the length of implant desired, an adhesive freearea 312 may be left in the central portion of the tube to create thecentral zone without bonding D1 shown in FIG. 23D with the advantages ofsuch a zone noted previously. A 30 mm length of adhesive free area ispreferred for a 4 cm length implant and 20 mm length adhesive free areafor a 3 cm implant. However, no adhesive free area is preferred for a 2cm implant; the adhesive should be applied to the entire surface of thesilicone tube 300 to achieve full lamination for that particularembodiment.

Pre-stretching the inner tubular layer compared to the outer layerallows the implant to exhibit axial elongation in use, such as undermanual pressure from the surface of the skin. This is because theimplant once released from the manufacturing fixtures will axiallyshorten, as the inner layer reverts to its resting configuration. Thiswill cause a microscopic or small scale accordion effect on the outerePTFE layer. The implant may thereafter be axially elongated bycompressing one end, or by over inflation, without the need for acompliant material as the outer layer. Elongation of the inner layerrelative to its resting state of at least about 10%, often at leastabout 25%, and in some embodiments between about 30% and about 70% maybe used.

FIG. 26G shows adhesive being applied to the end of the silicone tube300. Following application of the adhesive, the tube is smoothed with aclean room foam swab. The ePTFE 304 is then everted over the siliconetube using plastic tweezers 316, as in FIG. 26H and tape 318, preferablyTranspore tape, or 3M Microfoam, as in FIGS. 26I-J. The siliconeadhesive is then cured in a calibrated oven for at least 20 minutes at145-155° C. using the fixture, ceramic mandrel holder, and oven as wellas a timer, preferably a digital timer. Next, the adhesive is allowed tocool for approximately 5 minutes. The tied ends are then trimmed andremoved from the mandrel 336. Lubrication, preferably 99% IPA, is thenapplied. Next, the lamination subassembly created is visually inspected.A device is rejected if there are gaps between the ePTFE and thesilicone tubing inside, there are loose areas of ePTFE in the laminatedregion that are not attached to the silicone tubing, or excessivewrinkling and/or discoloration is observed. If the device is notrejected, the lamination may be sealed proximally.

The next step is to create an implant valve subassembly 346. FIG. 27Aillustrates various components that may be utilized in this process.First, a valve tube 141 is cut to a length of 0.30 inches. The valvetube 141 is then slid onto a 0.0345 inch diameter small needle 320, asin FIG. 27B. The tip of the small needle 320 is then inserted into thetip of a precision dispense tip, preferably a 20-gauge precisiondispense tip 322, more preferably a pink EFD tip, as in FIG. 27C. Thevalve tube is then transferred to the 20-gauge precision dispense tip322. Next, the tip of a 0.0415 inch diameter large needle 324 isinserted into the tip of the 20-gauge precision dispense tip 322, andthe valve tube 141 is then transferred to the large needle 324. The tipof the large needle 324 is then inserted into an 18-gauge precisiondispense tip 326, preferably a green EFD. Next, a valve plug 143 is cutto a length of approximately 1 inch. Using 4-0 silk suture 328, ahalf-hitch knot 332 is tied around the end of the valve plug 143, as inFIG. 27D. The suture 328 is then threaded through the 18-gauge precisiondispense tip 326 and the valve plug 143 is carefully pulled into theshaft, as in FIG. 27E. The valve 141 tube is then slid onto the valveplug 143 by simultaneously removing the removing the valve plug 143 fromthe shaft and pushing the valve tube 141 off the shaft, as in FIG. 27F.

Next, the valve tube 141/valve 143 plug subassembly is manipulated sothat there is no bunching and minimal bending. A 0.016 inch mandrel 330is then carefully inserted into the valve tube 141. Alternatively, a0.018 inch mandrel may be utilized. The mandrel 330 is slid through,taking care not to damage the valve tube 141 or valve plug 143. With themandrel 330 still in the valve tube 141, the mandrel 330 is insertedinto the 20-gauge precision dispense tip 322. The 20-gauge precisiondispense tip 322 shaft is then slid into the valve tube 141 withoutpushing out the valve plug 143. The mandrel 330 is then removed. FIG.27G shows the valve plug 143 trimmed so that it protrudes approximately1.5 mm from each end of the valve tube 141.

A neck tube 144 is then cut to 1.5 inches in length. Using the 4-0 silksuture 328, a half-hitch knot 332 is tied around the free end of theneck tube 144, and the free end of the neck tube 144 is slid halfwayonto the mandrel 330, as in FIG. 27H. Next, shown in FIG. 27I, thesuture 328 is threaded onto the 20-gauge precision dispense tip 322, andthe neck tube 144 is drawn into the shaft until the precision dispensetip 322 and the mandrel 330 about each other.

The valve tube 141/valve 143 plug subassembly is then transferred ontothe neck tube 144 by simultaneously removing the neck tube 144 from theshaft 322 and pushing the valve tube 141/valve 145 plug subassembly offthe shaft 322. Next, the tied portion of the neck tube 144 is cut off,leaving the free suture 328 inside the valve tube 141. The valve tube141/valve 143 plug assembly is then stabilized with fingers, and themandrel 330 is slowly slid through the subassembly taking care not todamage the valve tube 141, valve plug 143, or neck tube 144. The suture328 is then used to straighten out the valve plug 143 and to remove anybunches in the valve tube 141. The suture 328 is then slowly removedwithout moving the valve plug 143. The neck tube 144 is then trimmed sothat it extends past the valve tube by approximately 2 mm on one side,and 15 mm on the other side. Finally, the completed valve subassembly346, shown in FIG. 27J, is visually inspected, and rejected if any ofthe following characteristics are present: holes in the valve 141 orneck tubes 144, particulate and foreign materials inside the valve tube141, the valve plug 143 does not protrude from the valve tube 141 atboth ends, or the valve tube 141 is excessively bunched up.

The next step is to seal the proximal end 335 of the laminationsubassembly 336. Various components utilized in sealing the proximal end335 are shown in FIG. 28A. First, the subassembly 336 is inspected toensure the absence of moisture and that the lubricant 336 hasevaporated. A proximal shim 334 is then inserted into the laminationsubassembly 336 by lightly bending it lengthwise, as in FIG. 28B. Theproximal shim 334 is inserted until the neck protrudes out approximately2 mm, and the lamination subassembly 336 is then smoothed out so thatthe proximal shim 334 fits snuggly inside. The neck of the proximal shim334 is then aligned, as in FIG. 28C, so that it is parallel with theaxis of the lamination subassembly 336, making sure the shim 334 iscentered within the subassembly 336.

Next, shown in FIG. 28D, a hard jaw clamp 338 is placed across thelamination subassembly 336 approximately 1 cm from the end. The end ofthe lamination subassembly 336 is then filled with adhesive 340,preferably MED2-4213 adhesive, as in FIG. 28E spreading the adhesivearound the proximal shim 334. Next, as in FIG. 28F, the adhesive islightly smoothed out with fingers over the proximal shim 344 and theexcess wiped off using a lint-free wipe. The hard jaw clamp 338 is thenremoved and the lamination subassembly 336 is placed on a proximal sealfixture. Two or more 0.020 inch mandrels are then inserted as shimsbetween the two pieces of the proximal seal fixture 342, shown in FIG.28G. The top is then screwed down without distorting or creasing thedevice.

The lamination subassembly 336 is then cured in a calibrated oven for aminimum of 45 minutes at a temperature of 145-155° C. The fixture 342 isthen removed from the oven and placed on the copper cooling plate. Next,as shown in FIG. 28H, the proximal seal fixture 342 is blown with a coldair vortex tube as needed and the fixture 342 is allowed to cool beforeremoving the lamination subassembly 336. Next, the proximal shim 334 iscarefully removed from the lamination subassembly 336 and a razor bladeis used to trim off excess silicone adhesive from the end. Lastly, thesubassembly 336 is inspected and devices that exhibit significantasymmetry in the proximal tab, noticeable adhesive failure, excessadhesive migration into the expandable membrane, or cuts or tears in theexpandable membrane are rejected.

The next step is to insert the valve subassembly 346 into the laminationsubassembly 336. A 0.030 inch mandrel 334 is first inserted into thedistal end 348 of the lamination subassembly 336. Next, the 0.030 inchmandrel 334 is slowly slid into the neck of the proximal seal 337. As inFIG. 28I, a hypo tube 350 is then placed while the 0.030 inch mandrel isprotruding from the end proximal 335 of the lamination subassembly 336.The hypo tube 350 is then carefully inserted into the neck of thelamination subassembly 336 until approximately 1 cm is in the device.While the hypo tube 350 is in the lamination subassembly 336, the 0.016inch mandrel 330 (with the valve subassembly 346 on it) is slid onto thelamination subassembly 336 until the neck tube 144 is contained in thehypo tube 350, and the valve tube 141 abuts it, as in FIG. 28J. Afterthis, the hypo tube 350 is then slowly removed from the laminationsubassembly 336 while maintaining the position of the valve subassembly346.

Next, the hypo tube 350 is completely withdrawn, leaving the 0.016 inchmandrel 330 and the neck tube 144 contained in the neck of the proximalseal 337, shown in FIG. 28K. The valve subassembly 346 is then graspedthrough the lamination subassembly 336 and the 0.016 inch mandrel 330 isthen slid through the distal 348 end of the device without moving theneck tube 144 or the valve subassembly 346, as in FIG. 28L. Then, the0.016 inch mandrel 330 is then slid distally until it is approximately 6mm from the proximal end 335 of the device. A hard jaw clamp 338 is thenplaced approximately 4 mm from the proximal end 335 of the device.Adhesive, preferably MED2-4213 adhesive 340, is then placed in betweenthe neck tube 144 and the neck of the proximal seal 337, as in FIG. 28M.A second hard jaw clamp is then placed adjacent to the first hard jawclamp 338, ensuring that it is approximately 2 mm from the proximal end335 of the device. The lamination subassembly 336 is then placed in acalibrated oven and cured for a minimum of 20 minutes at between145-155° C. Next, the ceramic oven fixture is removed and allowed tocool. The hard jaw clamps are then removed from the device. Using arazor blade 352 as in FIG. 28N, the proximal tab of the device istrimmed along the proximal seal line 337, to a width of approximately1-1.5 mm.

Next, as in FIG. 28O, approximately 1.5 mm of the length of the tip ofthe proximal tab 140 is cut off using a straight cut, perpendicular tothe axis of the device. The 0.016 inch mandrel 330 is then carefullyslid toward the proximal end 335 of the lamination subassembly 336,taking care to ensure that the valve subassembly 346 remains on the0.016 inch mandrel 330. Lastly, the device is visually inspected fordefects such as an excessively asymmetrical proximal tab, noticeableadhesive failures, loose, unbonded ePTFE on the proximal tab, excessiveadhesive migration into the expandable membrane, and any cuts or tearsin the expandable membrane.

The next step is to seal the distal end of the implant. FIG. 29Aillustrates various components utilizable in the sealing process. First,the distance from the open end of the lamination subassembly 336 ismeasured to preferably 2 cm, 3 cm, or 4 cm, depending on the desiredinflated length of the implant. As in FIG. 29B, the laminationsubassembly 336 is then inserted into the distal seal fixture 354 sothat it protrudes past the clamping apex by the length of the desiredinflated implant (preferably 2 cm, 3 cm, or 4 cm). Next, the laminationsubassembly 336 is aligned on a base fixture within the inscribedguidelines. The distal seal fixture 354 in the preferred method supportsthe insertion of 5 devices, although a fixture may support any number ofdevices. When the lamination subassemblies are properly aligned, theclamping plate 358 is lowered and screwed into place, as in FIG. 29D. Anarbor press 356 may be used to aid in lowering the plate. Next, the openend of the device 336 is filled with adhesive 340, again preferablyMED2-4213. The adhesive 340 is then manually smoothed out lightly usingfingers. The excess adhesive 340 is wiped off using a lint-free wipe.Then, the seal plate 360 is lowered onto the devices and screwed intoplace, as in FIG. 29E. The lamination subassemblies 336 are then curedin a calibrated oven for a minimum of 45 minutes at 145-155° C. Thedistal seal fixture 354 is then removed from the calibrated oven andplaced on a copper cooling plate. Next, the distal seal fixture 354 isallowed to cool using the cold air vortex tube, as needed. Then, theclamp 358 and seal 360 plates are then unscrewed, and the laminationsubassembly 336 is removed. A trim end die is then used to trim thedistal tab 132. Lastly, the device is visually inspected for defectssuch as excessively asymmetrical tabs, noticeable adhesive failures,loose, unbonded ePTFE on the proximal tab, excessive adhesive migrationinto the expandable membrane, and any cuts or tears in the expandablemembrane.

The next step is insertion of a fill tube. With the 0.016 inch mandrelprotruding out of the neck tube on the proximal end, a 24-gaugecatheter, preferably a yellow Angiocath, is slid over the mandrel andinto the neck tube. A small amount of lubricant such as 99% IPA may bedistributed over the proximal end of the device, to make the device moretranslucent and also to facilitate insertion of the catheter. Next, thecatheter is then slid into the device ensuring the neck tube is notstretched out or the valve subassembly damaged. The catheter is theninserted until the valve subassembly is completely on the catheter tipand the catheter hub is within 2 mm of the proximal edge of thelamination subassembly. When the valve subassembly is entirely on thecatheter tip, the 0.016 inch mandrel will loosen and then be removed.The fill tube is then visually inspected, and rejected if the cathetershaft is permanently kinked or bent, or if the fill tube is protrudingpast the neck tube inside the expandable membrane (99% IPA can be usedto make the expandable membrane translucent).

The next step is to perform quality control testing on the fullyconstructed implant. Using a syringe filled with air, the implant isthen filled until it is inflated, but not pressurized. A digital caliperor snap gage is then used to complete the dimension verification. Animplant preferably should be within ±0.5 cm of its desired inflatedlength. The inflated diameter at the midpoint of the expandable membraneshould be preferably 4.5±1.0 mm. The proximal tab is preferably2.25±1.25 mm in width and 0.5±0.25 mm in thickness. The distal tab isalso preferably also 2.25±1.25 mm in width and 0.5±0.25 mm in thickness.Any implants not conforming to the above dimension criteria arerejected.

Next, the implants are subjected to pressure decay testing. At thebeginning of the shift, a leak tester, preferably a USON Sprint LC leaktester, is set to the following parameters: 3 psi test pressure, 5 secfill, 5 sec stabilize, 30 sec test, auto dump, 0.050 psi reject level,0.2 cc (0.05 cc/min) product volume. Next, the implant to be tested isconnected to the leak tester with a flexible hose and a luer connection.The start button on the leak tester is then pressed to run the test. Agreen light on the leak tester signifies a passing test; a red lightindicates failure. Implants that do not pass the pressure decay testshould be discarded. Once assembled and quality control testing iscomplete, the implant is ready for packaging and distribution, andeventual implantation.

Following is a method of implantation of an inflatable nasolabialimplant. In this embodiment, the patient's face is assessed by thephysician in both a seated and supine, or reclining position. Inparticular, the length, depth and course of the patient's nasolabialfolds are assessed by the physician. Next, a surgical pen is then usedto mark directly on the patient's face the proposed implantation. Markswill typically be made indicating the point of initial entry of theimplant, the point of exit of any delivery system components that makean exit through the skin and a line or lines that represent one or moreof the following: the desired central axis of the implant, the desiredmost lateral edge of the implant, the desired most medial edge of theimplant.

The physician then chooses the appropriate implant size and type, forexample from among the available range of Juva Medical FulFil products,which can be made in a range of diameters (stated by the nominal“circular” diameter when filled to the maximum recommended volume) andlengths (stated as the unstressed natural length; the nasolabial implantis constructed so as to allow axial elongation once implanted inresponse to tissue movement) as well as different curvatures andend-tapers or contours. The physician then delivers the implant by oneof several methods, which may be enabled by a delivery system.

One method of insertion is referred to as the “sew-through” method. Inthis method, the physician would first use the needle portion of aspecialized delivery system (said needle portion being may be providedas a stand-alone needle, a needle with an attached suture or a needleelement contained within a sleeve, cannula or at the distal end of shaftwhich contains other functional elements) to puncture through the skinat the desired entry location. The physician may choose to manuallypinch the skin in this location so as to allow the needle (which isstraight or relatively straight, in the latter case having a largeradius of curvature so as to match the anatomical curvature found in thenasolabial fold of some patients) to pass first along a path that issomewhat normal to the skin surface (at an angle of betweenapproximately 90 degrees and approximately 30 degrees) and then, oncethe needle tip has entered the subdermal tissue plane below the skin andbeing contained within the fibrofatty layer (adipose tissue) that liesbetween the dermis and the superficial musculoaponeurotic system (SMAS)that presents a higher resistance to the needle tip than does thefibrofatty layer, to then pass along a second path that remains withinthe fibrofatty layer tissue plane that is superficial to the SMAS anddeep to the skin. Horizontal line A of FIG. 25 illustrates a horizontalplane superior to the vermillion border of the lips. FIG. 26 is a crosssectional view, generally around line A in FIG. 25, and illustrates thevarious described subdermal tissue layers. Line B represents ahorizontal plane through the mandible.

In one embodiment, a delivery system can also be provided with aspring-coupled distal tip, or other force-based mechanism, that deflectswhen met with the increased resistance seen when the tip encounters theSMAS, thus steering the delivery system directly into the desiredsub-dermal tissue plane.

Once the tip of the needle element is within the subdermal plane, thephysician advances the needle or delivery system with needle tipextended, directing the tip toward the desired exit point. The physicianmay manually palpate the skin directly superficial to the path of thedelivery system so as to better guide it along the desired path and toverify that it is on said path.

In another embodiment, a combined delivery system is used. One or moredissecting elements that are constituents of the delivery system areexposed after having been previously in an unexposed state. For example,the distal end of one preferred embodiment has two blade-like elementsthat swing outward from a recessed cavity within the shaft of thedelivery system once said system is properly positioned in thesub-dermal plane. Activation of the first and second blade like elementsfrom a first, percutaneously advancing configuration to a second,dissecting configuration can be accomplished by axially distallyadvancing or proximally retracting a tube or core positioned coaxiallywithin an outer tubular body. Alternatively, a tissue dissection toolmay be provided with a fixed forked distal end, with a left blade and aright blade having a V shaped space in-between. The opposing radiallyinwardly facing edges of the blades are sharpened, while the radiallyoutwardly facing edges of the blades are blunt. The distal tips of theblade may be provided with an atraumatic end, such that tissue withinthe forked end of the blade is severed while surrounding tissue ispreserved. As described in greater detail elsewhere in this disclosure,these blades serve to collect and then cut the connective fibrous fibersthat are present in the fibrofatty layer and that are, in particular,distributed more densely in the tissue underlying the nasolabial fold(the deep attachment of said fibers being responsible for the “crease”that defines the nasolabial fold).

In an embodiment where a delivery system does not combine the dissectionelement or elements with the needle element, the needle element can beadvanced fully until it exits at the desired exit point, at which pointit is grasped either by the physicians fingers or by an instrument suchas needle holder and withdrawn from the patient. Attached at the back ofthe needle or delivery system that contains the needle element is asuture or other tension-carrying member such as a fine stainless steelwire; said member is of sufficient length so as to have an excess ofmaterial still present at the proximal entry side of the implantationsite after its distal attachment has exited from the distal exit point.For example, in the nasolabial fold, the distance between the entry andexit points will be between about 2 cm and about 7 cm, typically betweenabout 3.5 cm and about 5.0 cm, thus the suture or suture-like memberwill be provided in a length of between about 5 cm and about 20 cm.

The continued presence within the tissue of the suture or suture-likeelement following the distal withdrawal of the needle now serves todefine the location at which the implant will be placed as well as apath that may be taken by subsequent instruments or elements of thedelivery system, in much the same way that a guide-wire is used to guideintravascular catheters.

For example, a dissecting element can now be advanced over thesuture-like member and provide the same fiber-dissection as describedabove. Alternatively, a dissecting element can be inserted adjacent tothe suture-like member and directed by the physician to undermine thedesired tissue location and thus create a pocket or potential space forthe implant to be placed. (The tissue undermining and creation of apocket or potential space for placement of the implant was similarlyaccomplished in the alternative steps described above.)

Next, the placement of the implant can then be undertaken. In oneembodiment, the implant is provided already attached to the suture, suchas by having the suture pass through a distal tab portion, described ingreater detail elsewhere in this disclosure, said suture then eithercreating a loop (attached at the needle) or being tied and knotted atthe tab, or other attachment means.

In another embodiment, the implant is not provided already attached tothe suture. The suture is provided with a second needle in thisembodiment, said needle being either straight or arcuate as desired bythe physician. The physician then “takes a bite” with this needle anddraws the suture through a distal attachment tab on the implant andfollows that with an attachment means as described above.

The physician then draws the implant into the desired location byapplying tension to the suture. Said tension can be applied either bygrasping the original insertion needle (now having exited distally) orthe distal portion of the suture or both.

The implant can be aided in its entry into the proximal tissue entry bya funnel introducer which is constructed so as to urge the implant intoa tightly rolled or folded configuration. The funnel introducer can bepartially or fully pre-perforated or slit in one or more longitudinallines or in a helical path, allowing it to be removed from around theimplant or elements of the delivery system without requiring that it beretracted coaxially over said implant or elements.

In one embodiment, the implant can also be provided with a protectiverestraining sheath which causes it to remain in a tightly rolled orfolded configuration while stored prior to use. Upon removal of saidsheath, the polymeric materials of the implant will tend to remain in arolled or folded configuration, thus reducing the frictional dragbetween the implant and the tissue as the implant is inserted. Since thetransition at the distal end of the implant will cause the greatest suchdrag, the sheath may also be a partial sheath that restrains only adistal portion of the implant.

In another embodiment, the sheath may also be formed of a thin-walled,high-strength, relatively inelastic material such as polyethyleneterephthalate, polyamide, polyimide, polyethylene or similar materialsand may also have perforations as described above relative to the funnelintroducer, and have a pull-tab or pull-line thereby allowing theimplant to be inserted while the sheath (which may be full or partial)is still present. The sheath will act to reduce the diameter of theimplant/sheath assembly by holding the implant in a tightly rolled ortightly folded configuration and will also act to smooth out size andshape transitions, both aspects serving to reduce the frictional dragand other difficulties encountered during implant insertion.

Alternatively, the same function just ascribed to the sheath can beprovided by a binding element or elements, such as a fine filament, e.g.a small-diameter single or multi-strand fiber. Described elsewhere arespecific advantageous designs and arrangements of implant binding(s)which constraining the implant in a tightly rolled or tightly foldedconfiguration and also allow for removal of the binding(s) without undueforce (which would disturb the position of the implant, said implantbeing in its desired position when said bindings would be removed) orthe need for the implant to distort laterally to allow for unbinding.

A proximal suture or other proximal control element may also be present,for example by having a suture or suture loop attached to a proximalattachment tab of the implant.

The physician can assess implant location once it is inserted bothvisually and by manual palpation and, if desired, can adjust theposition of the implant using the distal suture or, if present, theproximal suture, or both distal and proximal sutures.

Once the physician has positioned the implant as desired and verifiedthat it is correctly positioned without having prolapsed on itself (thiscan be verified by locating the implant ends, which often can bepalpated by a trained physician and comparing it to the known length ofthe implant, said comparison potentially being performed with aJuva-supplied length template, or by palpating to assure that there areno lumps that would be indicative of prolapse), the inflation of theimplant with the desired can filler can be initiated.

The filler may be sterile normal saline or other liquid, a gas, such asair or carbon dioxide, or may be a mixture of liquid and gas. The fillermay also be a viscous material such as an oil, or a cross-linked ornon-cross-linked hyaluronic acid. The filler may also be a material thatwill polymerize and/or crosslink in situ, such as a mixture of twopolyethylene glycols or of dimethyl siloxanes or other siliconeelastomers.

The implant may have been prepared previously so as to removesubstantially all of the air present within it prior to inflating withthe filler. Such preparation can be accomplished in the typical fashionused with intravascular balloon catheters and referred to as “vacuumprep” or “aspiration prep.”

The implant is then filled to a volume as desired by the physician.Typically, fill volumes will be at or below a “maximum flaccid filllevel” that is provided for each implant size and type. Filling to thislevel or below creates a flaccidly filled implant which augments tissuevolume (thus effacing the nasolabial fold or other wrinkles overlyingthe implant) without creating undue stresses within the tissue. Since itis flaccidly filled within a pocket or potential space created by theprevious dissection step, the internal pressure within the implant isvery low, typically 1 psi or less, preferably much less than 1 psi, suchas 0.6 psi or less, 0.4 psi or less, or 0.3 psi or less. (The structuralintegrity of the implant is such that it can withstand much largerinternal pressures, however, in order to provide for a safety factor andin order to withstand momentary increases in pressure that could resultfrom contact of the patient's face with external objects. As describedelsewhere, the elastomeric portion of the implant has the capacity toelongate to a great degree in response to either overfilling or increasein internal pressure, and the sealing components of the implant canlikewise withstand such pressures.) As noted above, a preferredflaccid-filled implant may be filled to, for example, no greater thanabout 50%, 60%, 70%, 80%, or 90% of the maximum fill volume.

Next, the fill tube through which the filler was injected is thenremoved. The fill tube may be an elongate tube composed of one or morematerials, the distal material having a higher durometer or flexuralmodulus than the proximal material. For example, the distal portion ofthe fill tube, of between about 1 cm and about 4 cm in length, can be atube extruded from high-density polyethylene with an inside diameter ofbetween about 0.005″ and 0.020″ and an outside diameter of between about0.010″ and 0.040″. The distal portion of the fill tube can be heat-fusedto a longer proximal portion of tube extruded from low-densitypolyethylene with the same range of dimensions. Having a longer proximalportion to the fill tube serves to mechanically isolate the implant fromany disturbance that might occur to the proximal portion of the filltube, such as when the physician or an assistant is handling aninflation device, such as a syringe, which is attached to the fill tube,said isolation being enabled by the flexion of the tubing. LDPE orsimilar materials are advantageous in that they combine relatively highflexibility with relatively high kink-resistance. Kinking of the filltube is to be avoided as it would impinge on the lumen of the fill tubeand thus make implant inflation difficult. HDPE is advantageous for thedistal portion of the fill tube because it has sufficient hoop strengthso as to resist compression by the valve assembly (described elsewhere)and because it has relatively low coefficients of static and dynamicfriction, thus enabling the removal of the fill tube with minimum riskof disturbing the physical placement of the implant.

The attachment suture or sutures are then either removed from theimplant by cutting the suture loop and withdrawing the remainder of thesuture or are cut below the level of the skin by temporarily pushing theskin inward while cutting the suture, according to standard surgicaltechnique.

In an alternative embodiment, an alternative placement approach isreferred to as the “push through” method. This method may be usedinstead of the sew-through method or as an adjunct to it as will bedescribed below. When used as an adjunct to the sew-through method, inaddition to the traction applied by the distal suture and used to drawthe implant into place during the insertion step, as described above,the physician uses a grasping instrument to grasp the distal end of theimplant, for example by clamping across a distal tab of the implant,said instrument entering the tissue adjacent to the implant and throughthe same tissue entry point. It is advantageous that the graspinginstrument is a specially designed instrument disclosed herein.

The physician then inserts the implant by pushing the graspinginstrument into the tissue pocket (while continuing to grasp the implantdistal tab); the physician may provide supplemental force and/orguidance by means of the distal suture. Funnel introduction, sheathingand/or binding can also be used as described above. Once positioned asdesired, the physician releases the implant from the grasping instrumentand withdraws the instrument. The procedure continues as describedabove.

The push-through method can also be used without a distal suture. Inthat case, the initial skin incision may be made by a needle which thenis used to track on the desired path but does not exit distally, or by ascalpel blade. A pocket is then dissected, and then implanted in themanner described in the sew-through method above.

In another embodiment, also disclosed is a specialized graspinginstrument for use in placing an inflatable soft tissue implant. Keyadvantages of this design over currently available instruments will bepointed out in the course of the description which follows. As seen inFIG. 33, the detail view (area circumscribed by 168 of FIG. 32), theinstrument has its distal-most end a blunt tip 170 which allows theinstrument to controllably pass through the tissue bed under thephysician's control. The blunt, rounded tip 170 encourages theinstrument to remain within the selected tissue plane, which, in thecase of a nasolabial implant, is the sub-dermal plane. Existing graspingforceps may have flattened tips which, if held in improper orientation,can lead to exiting of the desired tissue plane.

The tip is attached or formed from the main tube body 172 of theinstrument which contains a curved slot 174 near its distal end. Thediameter of the main tube body 172 is ideally small enough to be able topass through an initial skin incision that would be formed by a smallsurgical needle or the tip of an 11-blade scalpel. Preferably, the sizeof said needle would be 16 g (approximately 0.065″ or 1.6 mm), 18 g, 20g, or smaller, as needle sticks of the skin of that size or smallertypically do not require suture-closure. It is desirable to avoidsuture-closure of the skin in an office-based or other minimallyinvasive cosmetic procedure as it reduces the possibility of temporaryor permanent scarring and obviates a return visit for suture removal.

Currently available grasping forceps have minimum dimensions of 2 mm ormore and are typically not circular in cross-section. For example, thesmallest “alligator forceps” or “micro-forceps” available found in aMarina Medical catalog are 2 mm×3 mm in its cross-section. Since theseforceps were not designed to be used in such a minimally invasiveprocedure as the implantation of the inflatable soft tissue implant,those dimensions are adequate. However, the disclosed grasper departsfrom typical surgical approaches by using a coaxial tube arrangement toprovide a small-diameter circular cross-section. The circularcross-section is also advantageous in that it allows the user to simplyrotate the product in order to move the grasping zone (which lies withinthe curved slot 174) away from the implant following implant release. Incontrast, existing grasping forceps use a jaw-like motion (similar to analligator's jaws) which requires a larger space within the tissue forthe open position than for the closed position. The need for a largerspace is a disfavored for the soft tissue implant for two reasons: thedissected pocket in which the implant is placed has been created withparticular attention to its width and thickness, because a mismatchbetween pocket size and implant size can lead to implant migration,prolapse or other shape distortion. Moreover, the opened jaw of anordinary grasping forceps is likely to disturb the position of theimplant, which it has just released as the forceps is removed from thetissue. The ability of conventional grasping devices to rotate thecurrently available grasping forceps in an attempt to “clear” theimplant and prevent this disturbance is thus severely limited because ofthe large extension of the open jaw out from the instrument's centralaxis.

The grasping function of the disclosed specialized grasping instrumentis enabled by the slidable advancement of the plunger 176 against thefixed grasping face 178. In one method of construction, the fixedgrasping face is the most proximal face of a separate tip element whichinclude the blunt tip 170 and which is press-fit, or slip-fit and welded(such as by laser welding) in the distal end of the main tube 172, orsome combination of those techniques, or of other attachment means suchas adhesive or mechanical fasteners.

The opposing faces of the plunger 176 and the fixed grasping face 178are constructed so as to be smooth, flat and parallel to each other soas to not endanger the implant by tearing or other mechanical damage. Incontrast, currently available grasping forceps have ridges or teeth onthe grasping surface, which may damage the implant.

The slot 174 shown is curved towards the proximal end of the instrumentso that the distal portion of the implant can be grasped while the moreproximal portion of the implant lies along the axis of the instrument,as it will be during the implantation procedure. A back-facing curvealso reduces the frictional drag that the implant will see upon releasefrom the instrument. This is advantageous because little or no forcesare applied to the implant once it is in the desired position;disturbing it through frictional drag or by catching it with protrudingportions of the delivery instrument would lead to incorrect positioning.The back-facing curve also makes the initial insertion of the distal tipof the implant (often a distal tab) into the slot 174 prior to insertioninto the skin more easily.

In the embodiment shown in FIG. 34, the grasping face of the plunger 176is held against the fixed grasping face 178 by spring force. In order toopen the grasping faces 176, 178 and insert the implant into thegrasping slot 174, the physician uses his/her thumb against the back(proximal-most) surface of the main handle 180 while using two fingersagainst the front (distal-most) surface of the secondary handle 184. Themain handle 180 is attached to the main tube 172 while the secondaryhandle 184 is attached to the plunger 176. Sliding the secondary handle184, and thus the plunger 176, in a proximal direction causes thegrasping faces 176, 178 to open and compresses the spring 182. Thespring 182 is chosen so as to provide sufficient grasping force to theimplant without exceeding that level of force that would cause damage tothe materials of the implant. By using a spring 182 to apply thegrasping force, the instrument prevents such damage. FIG. 35 is arepresentation of the grasper from an angular perspective, with keyelements also shown in FIG. 34. Current grasping forceps do not usespring closure but rather have a ratcheting mechanism, as in FIG. 40,which allows as much force as the physician applies to be placed on thematerial being grasped and then locking that force in by means of theratcheting mechanism.

In another preferred embodiment, FIGS. 36-39, the grasping slot 174 inthe distal tip region 169 circled in FIG. 36 is axially symmetric, incontrast to the asymmetric curved slot shown in FIG. 33. This axiallysymmetric configuration of the slot is shown best in FIG. 39,illustrating the axially symmetric slot 174, plunger 176, and fixedgrasping face 178. It allows an implant to be inserted in either anantegrade or retrograde fashion. In an antegrade method of implantation,the grasper is pushed through a single incision, pulling the distal tipof the implant, which drags behind the distal tip of the grasper. In aretrograde method of implantation, in addition to the initial implantpuncture, a second puncture is made, the grasper alone is insertedthrough it, advanced until its tip emerges through the initial,typically inferior puncture, at which point the implant is grasped andthen pulled into the tissue. The retrograde approach has the benefit ofnot requiring both implant and grasper to be present simultaneously in askin incision. In this embodiment, an alternate grasper handle positionis also disclosed as shown in FIG. 36, which may be preferred by somephysicians. The secondary handles 184, extend outwardly from the mainhandle 180, may be grasped with two fingers on their (distal-most)surface of the secondary handle 184, with one or more other fingers usedto support the main handle 180. The skilled artisan will note that thehandles 180, 184 depicted in FIG. 34 may also be adapted to have anaxially symmetric grasping slot 174. FIG. 37 is a cut-away view of thegrasper of FIG. 36, additionally showing a spring 182 and a plunger 176.FIG. 38 is a representation of the grasper embodiment of FIGS. 36 and 37from an angular perspective.

While one such preferred embodiment is shown, the key advantages of thedisclosed grasping instrument can be preserved in a variety of otherembodiments as well, such as FIGS. 40-43. For example, the handleportion could be moved into a position 188, 192 off the axis 186, 190 soas to move the physician's hands further from the patient's face andreduce the possibility of the patient's facial features obstructing themotion of the instrument. For example, handles of the type pictured inFIG. 40 or FIG. 41 could be used. In addition, the spring-closure couldbe replaced by a free-sliding mechanism that is manually locked by athumb-screw or similar locking mechanism, such as once the physicianjudged that appropriate grasping force had been applied. Alternatively,the ratcheting mechanisms could be used, such as FIG. 43 or particularlyif the implant materials were of sufficient strength so as to withstandthe forces applied across the smooth grasping faces.

Also, although a coaxial tube design has been described here, the sameadvantageous circular-cross section can be obtained using two slidingmembers that lie next to each other and are linked through a T-slot, asis commonly done in surgical instruments.

Another useful embodiment, particularly for delivery of inflatableimplants in the sub-orbital region such as tear-trough implants, is acurved version of the grasper. A gentle curve is desirable, such as onethat is a circular arc with a radius of curvature of between 2 and 6inches, preferably about 4 inches. For many facial applications inparticular those in the periorbital region, the instrument should not beexcessively long, such as having an arc length of between 2 and 6inches, preferably about 3 inches. In curved embodiments, the plungerelement will be constructed of a tight-mesh wound or braided cable so asto be able to curve and still carry column loading with only negligibleaxial compression. In the T-slot (upper and lower slidable members)embodiments, the two members can be formed from circular arcs as welland maintain the slidable motion of the straight embodiments.

Although the present invention has been described in connection withcertain specific embodiments, various additional embodiments andalterations to the described embodiments are contemplated within thescope of the invention. Accordingly, the scope of the invention is notintended to be limited by the foregoing, and is intended to extend tothe full extent of the attached claims.

1. A method of forming a tissue implant, comprising the steps of:providing an outer layer and an inner layer, the outer layer configuredto cover at least a portion of the inner layer and be exposed to nativetissue when the implant is introduced into a patient, the inner layerhaving a compliance which simulates tissue; and attaching the outerlayer to the inner layer at least a first point on the inner layer andat least a second point on the inner layer, such that followingattachment the inner layer compresses the outer layer between the firstpoint and second point and holds the outer layer in a compressed stateto permit elongation of the implant between the first point and thesecond point when the implant is stretched, up to a limit defined by theouter layer.
 2. The method of claim 1, wherein the outer layer comprisesePTFE.
 3. The method of claim 1, wherein the outer layer is configuredto cover the entire inner layer.
 4. The method of claim 1, wherein theattaching step is carried out with the outer layer being attached to theinner layer to create an accordion effect on the outer layer.
 5. Themethod of claim 1, further comprising the step of stretching the innerlayer prior to attaching the outer layer to the inner layer.
 6. Themethod of claim 5, wherein the attaching step is carried out while theinner layer is in an elongated state, so that releasing the inner layercauses the inner layer to compress the outer layer between the firstpoint and the second point and hold the outer layer in the compressedstate.
 7. The method of claim 1, further comprising the step of fillingthe implant with a filler to provide the implant with compliance whichsimulates tissue.
 8. The method of claim 7, wherein the filling step iscarried out after the implant has been introduced into a patient.
 9. Themethod of claim 8, wherein the filling step comprises introducing avolume of filler into the implant which is less than a maximum fillvolume of the implant, resulting in the implant being flaccidly filled.10. The method of claim 1, wherein the attaching step is carried outusing an adhesive.